CSEC Human and Social Biology [Second Edition] 9780198352921

Citation preview

Human

Social

and

Biology

®

for

CSEC Richard

Fosbery INCLUDES

Peter

Givens

Pamela

Mark

CD

Hunte

Morris

Angela

Ramjit-Delochan

0

C

0

V')

835292

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for

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26

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95th

28

p

a

in

a

B.1.6.9

National

Disease

14

16

18

..

20

2

4

~

t

6

8

10

(years)

Growth

Center

for

charts

Health

Prevention

12

Age

and

for

boys

Statistics

Health

in

and

16

18

20

girls

collaboration

Promotion

14

(years)

with

the

National

Center

for

(2000)

0

✔

Questions

1

A

doctor

23.

Use

calculates

the

growth

the

BMI

chart

for

for

four

boys

10-year-old

in

Figure

boys

B.1.6.9

as

and

13,

18,

T able

21

Making

and

B.1.6.4

Study

the

to

the

BMI

categories

for

the

four

girls

of

different

ages

each

have

a

13

and

16.

What

advice

would

the

BMI

of

24.

The

girls’

ages

the

answer

by

reference

to

the

doctor

growth

3

T able

Suggest

to

summarise

malnutrition

the

form

give

to

the

girls?

chart

for

girls

in

Figure

effects

to

of

will

all

help

on

the

malnutrition

body.

include

the

vitamin

Don’t

and

Explain deciencies

from

Unit

B.1

B.1.6.9 (pages

and

of

are

mineral

your

table

match

forget

10,

tip

boys.

with Three

a

forms

you determine

2

overeating

overweight.

BMI

kg

has

population

girls

variation

example,

and

64

and

65).

B.1.6.4.

two

ways

in

which

parents

contribute

to

their

children

becoming

overweight.

0

Talk

about

?

Discuss

The

the

with

World

Health

world’s

bulimia,

make

family,

have

friends

Organization

greatest

can

sure

your

health

very

people

eat

and

has

threats.

serious

teachers

identied

Eating

effects

on

the

the

statement

obesity

disorders,

young

epidemic

such

people.

below.

as

as

one

anorexia

What

can

be

of

and

done

to

properly? p

Figure

B.1.6.10

sedentary

energy

the

ways

content

obesity

Lack

of

…

of

life,

all

exercise,

foods

factors

with

that

high

fuel

epidemic

91

835292

CSEC

HSB

Unit

B

Topic

1.indd

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16:03

Undereating

and

Nutrition

overeating

Questions

1

What

is

meant

2

Define

3

What

is

the

cause

of

kwashiorkor?

4

What

is

the

cause

of

marasmus?

5

What

causes

6

Calculate

7

Identify

8

Give

9

Describe

a

balanced

diet?

malnutrition

obesity?

the

BMI

three

three

Discuss

uses

of

is

man

of

1.73 m,

who

with

associated

weighs

70 kg.

obesity.

BMI.

the

dietary

advice

a

nutritionist

might

give

to

an

obese.

health

the

a

explain

who

Caribbean

for

diseases

and

individual

10

by

risks

countries

associated

with

overeating,

especially

in

the

today.

Summary

Nutrition

●

A

balanced

out.

Energy

and

fats.

cells

●

The

is

The

and

provides

provided

diet

tissues,

essential

●

diet

fatty

must

in

acids

Vitamin

A

gums,

water;

is

also

for

are

provide

essential

making

for

for

B

energy

A,

D,

vision,

for

all

macronutrients

cell

vitamins

vitamins

needed

vitamin

the

including

micronutrients

soluble

enough

by

molecules

acids

minerals.

and

K

vitamin

respiration,

activities

we

carbohydrates,

for

for

making

carry

proteins

building

proteins

and

membranes.

and

E

biological

amino

the

–

are

C

vitamin

for

D

Vitamins

fat

making

for

B

and

C

are

soluble.

collagen

absorbing

and

in

skin

and

depositing

1

calcium

●

T wo

for

●

bone.

minerals

that

transporting

The

q

in

table

T able

Food

need

to

oxygen,

shows

the

be

and

tests

in

the

diet

calcium

for

are

for

iron

for

making

strengthening

identifying

food

haemoglobin

bones

and

teeth.

substances:

B.1.6.5

substances

Biochemical

Proteins

Biuret

test

copper

Starch

Iodine

–

test

sodium

sulphate

in

hydroxide

solution

and

solution

potassium

iodide

solution

(iodine

solution)

Reducing

fructose,

sugars,

maltose

Non-reducing

Lipids

(fats

Vitamin

●

Water

urea

sugars,

and

glucose,

Benedict’ s

is

e.g.

sucrose

Positive

result

reacting

with

oils)

Emulsion

required

in

the

in

the

gut

by

transporting

many

other

body

as

a

hydrolysis

blood

useful

sugar,

and

as

for

the

DCPIP

test after

acid

solution

breaking

major

hormones,

waste

s Benedict’

test

solvent,

and

with

hydrochloric

Decolourising

for

and

solution

lactose

C

molecules

plasma

e.g.

and

down

food

component

carbon

dioxide,

in

blood

salts,

substances.

92

835292

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HSB

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Topic

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Nutrition

●

●

Undereating

Dietary

The

fibre

cause

symptom

of

bacterium

in

●

the

prevents

of

many

food

leads

children

quantities

●

Body

of

in

to

in

against

the

including

bowel

diet.

food

poisoning

cancer.

Diarrhoea

poisoning

is

but

in

a

Anorexia

often

is

by

poor

it

by

variety

and

with

of

with

are

a

the

hygiene

dividing

T wo

result

of

or

are

disorders

their

even

as

young

extremes

reduce

such

body

the

lack

mostly

eating

normal

measures,

by

affects

anorexia

eat

is

complete

ways.

bulimia

bulimia

extreme

calculated

Obesity

A

malnutrition

People

people

is

required.

energy

women.

lose

(BMI)

undernutrition.

than

starvation

young

food

fibre

food

and

food

Protein

marasmus.

index

of

protects

of

disorders

overeating

considerably;

mass

and

lack

cause

energy

respond

and

mainly

intake

The

the

overeating

food.

starvation.

who

affect

food

more

to

kwashiorkor

that

of

includes

consuming

is

intestinal

Salmonella.

preparation

Malnutrition

of

constipation

constipation

and

large

vomiting.

mass

in

kilograms

2

by

●

(height

The

first

in

set

permanent

into

●

food

Each

The

the

●

such

of

on

activities

Regular

are

speed

the

in

These

are

molars

is

are

replaced

incisors

that

enamel

pulp

tooth

chew

that

cavity

above

full

the

and

food

a

cells,

gum,

the

that

bite

(mastication).

covers

of

by

canines

softer

blood

the

root

dentine.

vessels

is

the

and

part

of

bone.

feed

to

brushing

to

teeth.

teeth

hard

the

leading

as

of

and

is

teeth

visits

the

water

proteins

up

As

the

on

sugar

tooth

teeth

and

at

least

are

convert

Decay

decay.

dentist

catalysed

such

as

twice

a

essential

it

to

can

day

in

acid

be

which

breaks

prevented

and

using

identifying

by

dental

early

stages

of

affects

extends

into

over

below

or

associated

intestine

biological

without

end

of

a

catalysts

being

used

reaction

the

breakdown

triglycerides.

water

soluble

enzymes.

which

is

The

steeply

maximum

up

they

catalyse

This

of

large

food

converts

molecules

that

large,

can

be

rate

body

steeply

rate

from

of

of

reactions

low

temperatures

reaction

occurs

temperature.

because

they

After

are

at

the

37°C,

denatured

by

40°C.

enzymes.

stomach

pH

All

has

has

with

enzymes

an

an

have

optimum

optimum

enzymes

being

an

pH

pH

optimum

of

of

2.0

8.0.

denatured

and

pH.

trypsin

Activity

at

values

of

range.

consists

of

mouth,

(duodenum

(colon,

The

intestine

of

organs:

of

increase

37°C,

of

of

this

system

intestine

the

and

small

decreases

the

range

and

large

of

small

above

digestive

at

catalyse

proteins

into

activity

37°C.

into

the

The

small

to

activity

a

enzymes

enzymes

excess

secreted

secreted

pH

the

are

again.

the

enzymes

in

They

reactions

blood.

temperature

activity

Pepsin

up

cells.

unchanged

starch,

human

temperatures

pH

as

by

chemical

molecules

the

10°C

optimum

are

over

affects

by

of

system,

insoluble

T emperature

the

and

into

made

rate

they

digestive

absorbed

such

the

over

molecules

●

of

milk

with

tooth

enamel

reactions

●

the

crown

themselves.

●

covered

living

Enzymes

In

the

types

decay.

that

●

is

The

embedded

the

floss.

●

teeth

premolars

is

The

tooth

down

of

and

centre

Bacteria

of

teeth.

tooth

nerves.

metres)

and

rectum,

the

main

salivary

ileum),

regions

glands,

of

the

alimentary

oesophagus,

pancreas,

liver,

gall

canal

stomach,

bladder

and

anus).

93

835292

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Topic

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Undereating

and

Nutrition

overeating

●

The

mouth

moves

is

food

to

contraction.

acid

●

The

to

kill

small

surface

stores

●

Villi

lacteal

●

The

for

excess

which

acids

of

of

epithelial

digestion

the

(adipose)

Egestion

excretion

is

acids

glycerol

in

to

large

cells

are

liver

urea

is

of

has

be

and

acids

it

digestion

has

absorbs

the

a

very

muscular

by

of

by

blood

to

water

and

defecation.

increase

capillaries

protein.

large

remaining

anus

which

many

of

hydrochloric

the

and

one

digestion.

are

are

stored

so

into

into

in

the

the

body

liver

or

synthesised

used

excreted

recombined

waves

supplied

through

glycogen

they

as

microvilli,

villus

are

containing

well

intestine

with

oesophagus

chemical

assimilated

as

amino

the

juice

the

and

out

products

cannot

are

villi

each

stored

body;

body:

start

the

which

gastric

absorption

passed

absorption;

converted

and

The

of

to

for

many

are

transport

in

the

of

digestion,

peristalsis,

pepsin

food.

they

Glucose

amino

is

in

for

products

everywhere

●

until

by

secretes

adapted

composed

the

absorbed.

organs

and

is

absorbed

area

mechanical

stomach

bacteria

covered

surface

for

stomach

intestine

faeces

are

the

The

area

transport

adapted

are

to

after

is

into

make

through

the

into

kidneys;

and

are

proteins

plasma

deaminated

triglycerides

they

respired

in

all

proteins;

ammonia,

fatty

stored

in

fat

tissue.

is

is

the

the

removal

removal

of

of

undigested

waste

food

products

from

of

the

large

intestine;

metabolism.

94

835292

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Nutrition

Practice

9

Practice

From

t he

table

below,

features

which

best

Questions

describe

Questions enzymes?

Section

1

A

Which

of

t he

following

is

a

list

of

fat

soluble

Biological

Contains

Affected

Affected

catalyst

active

by

temperature

2

A,

B

B,

C

A,

D

B,

C,

E,

D,

C,

Which

by

û

ü

ü

û

K

K

D,

pH

vitamins?

A

A

sites

E,

K

B

û

û

ü

ü

C

ü

ü

û

ü

D

ü

ü

ü

ü

D

type

of

teet h

are

responsible

for

most

of

t he KEY

mechanical

digestion

in

t he

mout h? =

ü

A

û

3

B

molars

C

canines

D

premolars

The

10

=

NO

Which

of

of

salad

which

to

your

diet

can

help

in

t he

following

is

an

example

of

a

A

cellulose

B

starch

C

glucose

D

maltose

t he

disease?

constipation

B

rickets

C

diarrhoea

D

anaemia

Section

1 4

of

monosaccharide?

addition

prevention

A

YES

incisors

The

biuret

colour

test

change

is

carried

from

out

blue

to

on

a

sample

violet

is

of

seen.

milk.

This

B

a

Define

b

Malnutrition

t he

term

which

of

t he

following

nutrients

is

can

be

diet

caused

[2]

by

undereating

and

indicates overeating.

t hat

balanced

A

i)

Complete

t he

table

below

about

under

present? nutrition.

A

sugar

B

starch

C

fat

D

protein

Nutrient

Vitamin

Deficiency

Nutrient

Disease

food

source

A

Anaemia

5

The

enzyme

amylase

is

found

in

our

digestive

tract.

Kwashiorkor

Which

pH

A

pH

9

B

pH

3

C

pH

5

D

pH

7

does

t his

enzyme

work

best

[5]

ii)

Obesity

by

is

an

Someone

t he

lacking

vitamin

C

in

t heir

diet

can

healt h

deformation

in

t he

weakness

C

night

c

Identify

Harold

bleeding

Marasmus

is

A

lack

carbohydrates

B

increased

of

a

condition

due

to

D

of

t he

two

factors

obesity.

ot her

t han

diet

t hat

can

a

[2]

chocolate

determine

if

fats

muffin

(lipids)

for

are

breakfast.

present

in

He

his

Write

a

list

of

steps

for

t he

procedure

to

test

[3]

a

Distinguish

b

Explain

between

what

excretion

happens

in

t he

and

large

egestion.

intestines

[3]

of

t he

proteins

increased

of

to

lipids.

digestive

tract

Our

are

for

t he

formation

of

faeces.

[4]

calcium cells

i) All

is

iron

c

8

which

obesity

t he:

2

lack

caused

in

gums

for

C

wit h

way

[3]

bought

to

muffin.

7

person

disease

blindness wants

D

a

a

one

bones lead

B

of

of

Describe

experience: iii)

A

example

overeating.

affected.

6

Meat

at?

following

are

conditions

related

to

List

made

t hree

up

uses

of

of

almost

water

in

70%

t he

of

water.

body.

[3]

obesity

ii)

Name

two

diseases/conditions

t hat

are

caused

except:

by A

coronar y

B

ast hma

hear t

a

lack

of

Give

t hree

conditions diabetes

D

hyper tension

in

t he

diet.

[2]

disease

iii)

C

water

signs

or

named

symptoms

in

(c)

(ii)

of

t he

above.

diseases/

[3]

95

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Practice

3

We

Nutrition

Questions

need

to

balanced

only

t hree

a

i)

eat

diet

a

is

balanced

made

undergo

t he

diet

of

for

us

different

to

be

healt hy.

nutrients

of

A

which

a

Name

b

What

digestion.

Complete

products

up

t he

of

following

table

t hat

are

about

t he

absorbed

c

into

What

b

[3]

d

End

product

of

is

Delroy

A

to

name

B?

D

of

on

t he

t he

diagram.

enzyme

[4]

released

by

t he

par t

[1]

t he

above?

t he

Nutrient

par ts

t he

labelled

digestion

bloodstream.

t he

is

function

of

t he

enzyme

named

in

[1]

had

blank

a

slice

spaces

of

in

fish

t he

as

par t

diagram

of

a

meal.

below

Fill

which

in

shows

digestion

stages

in

t he

digestion

of

t he

protein

in

t he

fish.

[6]

Carbohydrates

Proteins

1.

Mouth:

Teeth

crush

2.

Stomach:

Enzyme___________

Fats and

grind

smaller

ii)

Name

two

balanced

each.

b

Food

i)

and

give

a

present

food

in

source

pieces.

a

for

for

consumption

must

be

done

under

conditions.

Make

when

ii)

diet

nutrients

into

[4]

prepared

hygienic

ot her

food

a

list

Diarrhoea

infection

hygiene

two

of

4

hygienic

preparing

is

in

a

food.

condition

t he

during

gut

by

food

practices

a

caused

vir us

by

due

preparation.

signs/symptoms

to

PROTEIN

follow

[4]

of

t his

an

to

poor

Suggest

disease

and

3.

two

Small

the

measures

of

treatment

t hat

can

be

taken.

Intestines(I):

______________

enzyme

4.

juice

contains

_____________

diagram

below

shows

t he

human

alimentar y

juice

contains

the

that

polypeptides

to

__________________

peptides.

The

intestines(II):

[4] converts

4

Small

Intestinal

e

The

digested

from

the

the

materials

alimentar y

bloodstream.

allow

5

to

_____________________.

canal.

Samuel

them

ate

a

to

of

the

canal

State

absorb

hamburger

protein

through

THREE

features

digested

for

are

the

of

materials

lunch

at

absorbed

villi

and

the

into

villi

that

quickly.

[3]

school.

B

a

Name

b

Explain

teet h

two

in

major

how

his

Samuel’s

toot h

to

i)

t he

are

different

involved

brot her

for

t hey

toot h

of

present

in

his

types

in

meal.

[2]

of

mechanical

[4]

little

ac hes

dentist,

each

mout h

digestion.

c

nutrients

some

found

Keron

time.

out

has

Af ter

t hat

been

having

c hec king

Keron

had

a

wit h

cavity

a

due

decay.

Describe

t he

process

of

toot h

decay.

[5]

A

ii)

Make

a

follow

list

to

of

care

four

for

guidelines

his

teet h

for

and

Keron

prevent

to

any

D

ot her

cavities.

[4]

C

96

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CSEC

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Unit

B

Topic

1.indd

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16:03

Unit

B

The

B.2

B.2.1

The

exchange

respiratory

(gas

structure

of

the

exchange)

breathing

and

gas

system

Learning

system

By

the

end

should

Are

you

a

rst

aider?

If

you

are,

you

will

know

what

to

do

if

someone

in

an

accident

and

stops

breat hing.

You

should

also

know

of

this

able

topic

you

to:

is

●

involved

be

outcomes

explain

the

importance

of

why

breathing

breat hing

out

expired

air

into

someone

else’s

lungs

will

help

to

keep

●

t hem

alive.

This

chapter

deals

wit h

t he

impor tance

of

how

we

relate

the

breathing

and

what

happens

to

t he

oxygen

t hat

t he

trainee

rst

aiders

structures

of

system

their

the

breat he

watching

to

t he

functions

demonstration

in

t he

photograph

may

one

day

have

to

provide.

●

distinguish

breathing,

Structure

of

the

respiratory

(breathing)

between

gas

exchange

and

system respiration

Breathing

is

t he

exchange

of

surface

t he

ow

oxygen

of

and

air

in

and

carbon

out

of

dioxide

t he

by

lungs.

Gas

diffusion

at

exchange

t he

gas

is

t he

●

explain

vital

In

in

humans,

lungs

and

nasal

cavity:

small

hairs

cells

stale

dust

also

moistens

and

a

air

in

carbon

is

in

fresh,

t he

lungs,

par t

oxygen-rich

dioxide,

is

air

removed

t he

from

to

leading

capacity.

our

into

our

lungs.

of

to

tube

middle

ear

good

that

warmed

palate:

nasal

closes

opening

when

swallowing

p

Figure

B.2.1.1

demonstrates closes

A

first

mouth

aid

to

instructor

mouth

larynx

breathing when

by

respirator y

brought

Eustachian

soft

epiglottis:

meant

air;

so

is

of

is

opening

bacteria;

very

supply

inspired

rich

surface

ensures

goblet

mucus)

trap

blood

air,

exchange

which

contains

(secrete

contains

gas

system

and

is

lungs.

t he

(breat hing)

what

exchange

–

closing

the

nostrils

and

swallowing

tilting

back

the

head

of

the

model

oesophagus

larynx:

contains

vocal trachea

cords.

When

air

passes

Key over

and

them

they

speech

terms

!

vibrate

results

Breathing

bronchiole

bronchus

diaphragm

in

and

Gas left

out

of

movement

ribcage

the

exchange

to

of

the

move

air

lungs.

The

diffusion

lung

of

rib

oxygen

between

intercostal

The

and

and

air

carbon

and

blood

dioxide

in

the

lungs.

muscle

alveoli

pleurae:

which

contain

cushions

diaphragm

fluid

muscle

lungs diaphragm

when

p

breathing

Figure

B.2.1.2

breathing

A

vertical

section

through

the

head

and

thorax

showing

the

system

97

835292

CSEC

HSB

Unit

B

Topic

2.indd

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08/01/2015

16:05

The

structure

of

the

breathing

and

gas

exchange

The

The

system

terms

respiration

remember

t hat

and

breat hing

respiration

is

t he

are

respiratory

of ten

process

t hat

(gas

confused.

occurs

exchange)

You

inside

system

should

cells,

oesophagus

no

cartilage

reduce

to

t hroughout

t he

glucose

fat).

and

to

release

Breat hing

is

energy

t he

ow

from

of

air

nutrient

into

and

molecules

out

of

t he

(mostly

lungs

friction

brought with

body,

about

by

movement

of

t he

diaphragm

and

ribcage.

oesophagus

cartilage:

Breat hing

supports

trachea

is

also

in

in

is

known

t hrough

also

as

t he

known

as

expiration

mout h

inspiration

and

and/or

and

exhalation.

nose,

passes

inhalation;

Dur ing

t hrough

breat hing

inspiration

t he

t hroat

air

out

ows

and

lar ynx

lumen

and

to

inner

lining

into

end

in

dust

tiny

air ways

poc kets,

t hat

called

extends

alveoli.

into

You

t he

can

dept hs

trace

of

t his

t he

lungs

pat hway

in

B.2.1.2.

bacteria

Figures trapped;

cilia

beat

to

B.2.1.2

plus

debris

B.2.1.3

Transverse

the

B.2.1.3

t he

show

head

and

t he

str uctures

t horax

t hat

(chest).

are

The

involved

upper

in

respirator y

tract

oesophagus

as

far

as

t he

lar ynx;

t he

lower

respirator y

tract

extends

from

t he

sections

top through

wit hin

upwards

extends

Figure

and

drive

breat hing

p

air

of

epithelium;

and

mucus

system

of

Figure ciliated

a

and

of

t he

trachea

to

t he

alveoli.

Table

B.2.1.1

describes

t he

str ucture

and

the

functions

of

t he

par ts

of

t he

respirator y

tract.

trachea

q

T able

Name

Study

✔

B.2.1.1

of

part

Figures

and

T able

names

B.2.1.2

B.2.1.1

and

and

functions

of

the

human

Structure

respiratory

Function(s)

and

to

functions

learn

of

Made

the

of

nine

muscles;

B.2.1.3

Trachea

A

wide

rings

these

tube

of

pieces

contains

of

the

stiffened

cartilage

vocal

by

and

Vocal

cords

in

the

gas

vibrate

and

produce

sound

cords

C-shaped

Allows

cartilage

air

bronchi.

to

ow

from

Cartilage

C-shaped

structures

tract

tip

Larynx

Use

Structure

ring

throat

holds

allows

the

the

to

tube

open.

oesophagus

exchange behind

it

to

expand

when

it

carries

food

system. (see

Bronchi

T wo

branches

surrounded

for

Bronchioles

of

by

the

Allows

trachea

blocks

of

(singular:

thin

tubes

to

ow

in

single

branching

air

layer

surrounded

from

the

Allows

air

to

ow

between

of

by

sacs.

thin

Lined

cells

blood

Gas

by

exchange

diffuses

and

dioxide

capillaries

alveolar

mucus-secreting

goblet

The

diaphragm

out

of

of

t he

tissue;

t he

ribs

The

Ciliated

separates

t he

lungs.

it

is

to

t he

t horax

diaphragm

The

central

surrounded

t he

t he

bronchi

B.2.1.4).

by

sternum.

move

trachea,

Figure B.2.1.4

of

and

contract

Figure

out

of

each

bronchi

and

from

t he

from

occurs

air

diffuses

to

here

blood;

from

–

oxygen

carbon

blood

into

the

air

abdominal

cavity.

cell

Movements

p

and

alveoli

Blind-ending

a

air

support

Very

alveolus)

B.2.1.3)

lung

cartilage

bronchi

Alveoli

Figure

The

par t

t he

of

t hick

up

ribcage

t he

t he

and

t hat

ribs

are

is

air

is

a

to

joined

t he

ow

tough

to

t he

intercostal

into

and

brous

sheet

backbone,

muscles

t hat

down.

bronchioles

mucus-secreting

cause

diaphragm

muscle

Between

ribcage

and

and

are

cells

lined

make

by

a

ciliated

sticky

epit helium

mucus

t hat

(see

covers

epithelium

t he

to

epit helium.

t he

mucus.

mucus

ver y

air

along

Gas

from

of

par ticles

cilia

beat

air ways

way

to

of

back

and

towards

protect

t he

dust,

t he

pollen,

for t h

in

t hroat.

lungs

bacteria

a

coordinated

This

against

and

vir uses

way

epit helium

damage

from

to

stick

move

provides

par ticles

a

in

t he

infection.

exchange

Sections

full

The

t he

effective

and

Small

t hrough

air.

Lung

t he

tissue

lungs

is

like

ver y

t he

one

spongy

in

and

Figure

most

of

B.2.1.5

what

show

you

t he

can

lungs

see

as

lling

98

835292

CSEC

HSB

Unit

B

Topic

2.indd

98

08/01/2015

16:05

The

t he

respiratory

upper

t heir

can

par t

ver y

right,

widen

of

when

t he

allow

you

system

photograph

There

folded

blood

a

you

are

air

to

sections

two

internal

more

are

The

linings

reach

t hrough

bronchioles

t he

so

at

during

alveoli.

t he

t he

deep

The

alveoli

bottom

‘tube’

of

the

breathing

t his

fairly

t he

alveoli

constant

breat he

of

process

direction.

oxygen

t hat

it

in,

air

out

oxygen

oxygen

around

The

t hat

has

Follow

so

t hat

enter ing

t he

t he

concentration

alveoli

and

t he

blood

it

can

t he

air

of

a

inside

is

oxygen

alveoli

recoil

t hat

of

makes

little

to

occurs

air

in

carbon

into

t he

t he

is

constantly

and

carbon

t hem

help

exchange

and

t hey

a

cross

refreshed

out

a

bit;

some

of

owing

lungs

t hrough

and

enters

t he

carbon

all

t he

has

about

blood

dioxide

t he

in

70%

carries

blood

t he

of

opposite

t he

carbon

total

dioxide

tissue.

in

owing

During

into

diffuses

respiring

capillar y

time.

Figure

passed

B.2.1.6.

t he

alveolus.

p

is

blood

t hat

has

been

pumped

by

t he

hear t

to

t he

Figure

Oxygen

dissolves

in

t he

lm

of

water

lining

t he

B.2.1.5

alveolus.

and

tissue

showing

transverse

bronchioles

Oxygen

diffuses

gradient

t he

cells

plasma,

down

t hrough

t hat

and

line

t he

its

alveolar

sections

and

a

blood

through

vessel

cells

t he

capillar y,

lining

surface

t he

t he

blood

Oxygen

two

(x18)

alveolus,

blood

membrane

of

t he red

red

of

tissue

concentration

t he

cell

Photomicrograph

lungs.

lung

4

system

dioxide.

enlarge

push

alveolus

dioxide

deoxygenated

oxygen

blood

t he

and

ows

This

while

dioxide

from

alveolus

carr y.

pat hway

Deoxygenated

carbon

diffuses

absorbed

t he

This

3

gas

vessel.

breat he

capillaries

2

and

wit h

lef t

breat hing

t hird

structure

air.

Exchange

1

t he

ventilates

achieve

When

exchange)

linings.

have

to

a

Breat hing

to

of

t hin

which

section

(gas

blood

cell

cell.

combines

temporar ily

wit h

capillar y

haemoglobin

to

for m

oxyhaemoglobin.

The

movement

oxygen

red

blood

cell

transpor ts

oxygen

to

5

in

Blood

t he

is

alveolus

body.

now

movement

carbon

of

dioxide

respir ing the

cells

of

into

out

of

the

alveolus

fully

saturated

wit h

oxygen

2

and 4

ows

into

a

vein

t hat

takes

blood

from

diusion

t he

oxygen

3

lungs

back

to

t he

of

into

diusion

the

blood

carbon

from

Features

of

gas

of

hear t.

exchange

dioxide

the

blood

surfaces

cells

The

alveoli

share

t he

following

lining

the

characteristics alveolus

wit h

t he

gas

exchange

surfaces

of

ot her

ver tebrate

animals.

●

A

ver y

space

large

for

surface

molecules

area

of

so

t here

carbon

is

plenty

dioxide

of

and

p

oxygen

t hese

●

A

to

diffuse

gases

ver y

t hat

good

oxygen

and

–

are

blood

t his

maximises

exchanged

supply

carbon

to

dioxide

t he

volumes

between

maintain

between

air

and

blood

B.2.1.6

Gas

exchange

in

an

alveolus

blood.

concentration

t he

Figure

of

and

gradients

t he

air

in

for

t he

alveoli.

Key

term

! ●

A

lining

A

t hin

t hat

is

permeable

to

oxygen

and

carbon

dioxide.

Deoxygenated ●

lining,

so

t here

is

a

shor t

distance

for

t he

molecules

to

has

The

lining

of

the

alveoli

is

made

of

ver y

thin

cells

that

are

similar

to

the

cells

about

blood

it

dioxide

that

line

capillaries.

These

two

layers

of

thin

cells

separate

air

blood

Blood

that

diffuse.

from

70%

can

than

of

carry

is

in

the

and

maximum

more

carbon

oxygenated

blood.

blood.

99

835292

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B

Topic

2.indd

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The

structure

of

the

breathing

and

gas

exchange

The

The

effect

of

gas

composition

from

Table

q

The

system

t he

of

t he

composition

B.2.1.2

T able

exchange

shows

B.2.1.2

air

of

t hese

of

Inspired

Oxygen

21

dioxide

Nitrogen

Water

%

%

vapour

alveoli

you

air

breat he

t hat

you

inspired

and

the

out

exchange)

composition

(expired

breat he

expired

air

in

air)

of

system

the

air

differs

(inspired

air).

air

Expired

air

16

0.04

4

79

79

Variable

(depends

on

the

Saturated

humidity)

with

evaporated

T emperature

Variable

Warm

Purity

Variable

Most

Practical

to

on

(gas

differences.

Component

Carbon

the

t hat

t he

Comparison

%

in

respiratory

dust

water

from

the

particles

vapour

lining

of

that

the

has

airways

removed

Activity

disinfected

Showing

that

expired

air

contains

more

carbon

dioxide

than

inspired

air

mouthpiece

Requirements

●

apparatus

●

lime

●

dilute

Lime

lime

p

Figure

B.2.1.7

apparatus

for

inspired

and

The

of

shown

in

Figure

B.2.1.7

two

●

solution

water

pieces

sign

turns

of

disinfectant

milky

when

eye

●

carbon

dioxide

is

(+)

of

paper

drawn

on

with

each

a

plus

one

protection

passed

into

it.

water

‘huff

and

carbon

expired

1

Sterilise

2

Put

3

With

a

a

clip

mouthpiece

on

your

and

nose

or

attach

hold

it

to

your

the

nose

apparatus

with

your

on

the

apparatus.

fingers.

puff’

comparing

concentrations

as

water

dioxide

your

several

in

mouth

over

the

mouthpiece,

breathe

gently

in

and

out

times.

air

4

In

Observe

which

ask,

breathing

6

Clean

and

A

until

out

or

B,

B

as

does

asks

pieces

you

the

have

apparatus

the

steps

to

breathe

to

disappear

and

2,

in

of

Douglas

are

shown

out

in

The

student

and

the

the

the

into

the

breathe.

lime

water

turned

and

refill

paper

it

with

turn

milky

rst?

Y ou

can

continue

milky.

with

the

limewater,

crosses

sterilise

drawn

on

the

mouthpiece

them

underneath

used

an

4,

but

this

time

mouthpiece.

tubes

results

A

and

you

start

Time

a

timer

how

as

long

it

soon

takes

as

for

you

the

start

cross

B.

obtain.

1

air

to

collect

empty

samples

Douglas

bag.

of

air.

The

In

bag

an

investigation,

was

tted

with

a

student

ow

valves

diagram.

breathed

volume

the

skills

of

bags

and

both

explain

Composition

breathed

3

through

Maths

as

and

flasks.

Repeat

Record

A

both

the

place

both

7

flasks

of

air

out

four

inside

in

times

the

into

bag

the

was

bag.

The

measured.

bag

A

was

sealed

sample

of

air

100

835292

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HSB

Unit

B

Topic

2.indd

100

08/01/2015

16:05

The

respiratory

from

the

bag

(gas

was

exchange)

analysed

system

for

the

The

composition

of

oxygen,

structure

of

the

breathing

and

gas

exchange

carbon atmospheric

dioxide

and

system

air

nitrogen.

valve

The

the

student

then

exercise,

the

did

some

student

vigorous

repeated

exercise

the

for

5

procedure

minutes.

to

collect

Immediately

a

second

after

sample valve

of

air.

The

In

both

results

cases

of

the

his

breathing

investigation

rates

are

was

shown

12

in

breaths

T able

per

minute.

air

bag

B.2.1.3.

of

q

T able

breathed

B.2.1.3

for

collection

breathed

breathed

Sample

of

exercise

out

out

air

air

air

p Before

out

After

Figure

B.2.1.8

This

student

is

filling

a

exercise

Douglas

bag

with

expired

air

3

Volume

of

air/cm

2000

15 000

3

Mean

volume

of

air

per

Percentage

of

oxygen

Percentage

of

carbon

Percentage

of

nitrogen

1

Calculate

the

2

Calculate

the

Douglas

3

The

4

air

Calculate

Use

figures

samples

to

15.3

3.6

5.5

74.9

74.7

in

the

air

into

table

the

per

in

breath

the

compared

the

student’s

the

calculate

of

change

exercise

moved

volume.

the

volume

percentage

after

of

500

17.2

dioxide

mean

bag

volume

breath/cm

for

minute

the

volume

volume

with

lungs

after

in

of

air

collected

in

the

before.

1

minute

volume

percentage

of

exercise.

oxygen

is

called

before

of

and

oxygen

absorbed

by

the

after

in

the

the

minute

exercise.

two

student

in

3

dm

5

per

minute

Calculate

the

before

volume

and

of

after

carbon

exercise.

dioxide

breathed

out

by

the

student

in

3

dm

In

a

the

per

separate

air

he

alveolar

●

air

those

Vital

air

B.2.1.9

is

the

This

exercise.

student

air

is

carbon

●

the

percentages

rst

out

you

is

as

in

sample

much

as

have

using

capacity

in

not

and

t he

air

much

just

a

is

breat hing

move

It

14%

the

breat hing

af ter

out.

after

from

collected

the

only

alveoli.

the

The

very

last

part

composition

of

of

his

of

of

dioxide

oxygen

expired

air

5.6%

and

that

carbon

he

nitrogen

●

dioxide

are

80.4%

different

from

collected.

capacity

Breat he

Vit al

and

was:

why

in

before

investigation,

breathed

oxygen

Explain

The

minute

t he

out

tot al

to

can.

you

your

is

lungs

volume

of

take

a

ver y

Now

breat he

is

your

vital

her

vital

out

record

This

Now

can.

maximum

fully.

of

you

as

breat hed

meter

in

as

air

volume

t he

breat h

hard

capacity.

of

air

of

t hat

air

breat hing

lungs

as

as

The

by

you

girl

in

can.

Figure

capacity.

volume

when

your

deep

out

because

can

t hat

as

be

deeply

you

exhaled

you

can

can

as

possible.

never

breat he

3

out

all

alveoli

It

is

to

a

t he

air.

There

is

always

about

1

dm

remaining

to

keep

your

inated.

possible

band

volume

to

record

around

of

your

p

your

your

chest

breat hing

chest.

are

As

you

recorded

movements

breat he

on

a

in

char t

by

and

attaching

out

(Figure

t he

a

Figure

B.2.1.9

Measuring

vital

capacity

sensor

changes

in

B.2.1.10).

101

835292

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The

structure

of

the

breathing

and

gas

exchange

Yo u

The

system

can

see

from

t he

Figure

B.2.1.10

respiratory

t h at

t he

(gas

p er so n

exchange)

b reat h ed

in

system

and

ou t

3

about

50 0 cm

while

breat hing

n o r mally

(t h is

volume

is

3

1

as

t he

3

dm

tidal

volume)

and

t h ey

3

Note:

It

is

age.

p

kn own

Figure

B.2.1.10

movements

Volume

recorded

of

over

a

vit al

c apac it y

of

50 0 0 c m

3

1dm

=

possible

Such

h ave

1000

to

cm

predict

calculators

a

person’s

are

vital

available

as

capacity

based

on

t heir

height

and

apps.

chest

time

Practical

Measuring

tidal

Activity

volume

and

vital

capacity

Requirements

3

bell

jar

plastic

(or

large

●

bell

jar

●

a

●

three

1

Set

marked

in

dm

trough

●

tubing

●

dilute

solution

of

disinfectant

wedges

up

the

apparatus

as

shown

above,

ensuring

that

the

water

level

is

on

container)

the

scale.

Sterilise

the

mouthpiece.

3

volume

scale /dm

2

Record

the

initial

3

T ake

4

Measure

5

This

6

Repeat

steps

volume

can

volume.

blow

a

deep

breath

then

breathe

out

fully

through

the

mouthpiece.

here

the

decrease

in

volume

in

the

bell

jar.

tubing

3

connected

to

is

your

vital

capacity

in

dm

disinfected

water mouthpiece

wedge

free

of

to

to

4,

only

this

time

exhale

normally,

so

that

the

tidal

be

measured.

water

Ask

p

1

allow

circulation

Figure

B.2.1.11

measuring

vital

Apparatus

capacity

for

and

other

capacity

students

and

tidal

in

your

class

volumes.

to

Use

use

an

the

app

to

apparatus

predict

to

their

measure

vital

their

capacity

vital

and

see

tidal

how

many

match

the

predictions.

Now

try

Maths

skills

2.

volume

Maths

Is

there

a

correlation

Researchers

referred

to

age;

sample

q

of

T able

BMI

calculated

they

correlation

in

the

a

the

BMI

people

vital

North

determined

between

the

2

between

measured

hospitals

researchers

and

skills

BMI

and

vital

capacities

American

predicted

the

and

BMI

of

vital

are

over

for

person

vital

300

lung

capacity

each

predicted

investigated

of

city

capacity?

from

to

in

each

see

capacity.

shown

people

function

T able

if

The

who

were

tests.

The

person’s

there

is

results

height

any

for

a

small

B.2.1.4.

B.2.1.4

Vital

of

capacity/%

BMI

predicted

Vital

of

capacity/%

BMI

predicted

Vital

of

capacity/%

predicted

50

61

35

95

20

96

56

75

30

85

22

130

45

90

31

98

52

77

42

84

25

82

27

92

43

102

24

110

38

75

1

Describe

2

Plot

how

these

the

results

researchers

on

a

calculated

scattergraph

with

the

BMI

BMI

on

of

the

each

person.

horizontal

axis.

102

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The

respiratory

(gas

exchange)

system

The

breathing

mechanism

a 2

3

Do

you

the

think

there

evidence

for

is

a

your

correlation

between

BMI

and

vital

capacity?

Give

answer.

3

Suggest

the

limitations

5

Suggest

the

problems

of

the

that

information

people

with

a

in

T able

high

md / ria

4

B.2.1.4.

BMI

might

have

with

their

fo

1

emulov

breathing.

Questions 0

0

1

Refer

to

Figures

B.2.1.2

and

B.2.1.5

to

list

the

pathway

taken

by

10

20

30

40

50

60

a time / s

molecule

of

oxygen

from

the

atmosphere

to

the

gas

exchange

surface. b 2

2

Refer

gas

to

Figure

exchange

B.2.1.6

in

the

to

list

the

route

taken

by

carbon

dioxide

during

lungs. 3

Refer

to

are

4

What

the

5

Distinguish

6

Some

adapted

role

of

the

between

students

and

for

B.2.1.6

gas

in

the

exchange

investigated

describe

three

ways

in

which

exchange.

cartilage

gas

to

the

trachea

and

and

in

the

1

emulov

is

well

B.2.1.5

fo

alveoli

Figures

md / ria

3

bronchi?

breathing.

breathing

of

a

16-year

old

male

athlete. 0

Figure

B.2.1.12a

shows

his

pattern

of

breathing

for

a

minute

0

when

10

20

30

40

50

60

time / s

resting.

took

Figure

some

B.2.1.12b

shows

the

pattern

of

his

breathing

while

he

exercise.

p

Figure

of

a

Make

a

table

to

compare

his

breathing

at

rest

and

during

a

●

●

●

b

in

the

volume

the

rate

the

volume

of

of

the

breathing

when

The

air

breathed

breathing

Calculate

B.2.2

air

in

percentage

he

in

takes

with

breaths

breathed

in

each

per

resting

change

in

a

breat hing

each

of

Include

these

your

aspects

answers

of

in

exchange

1

minute

while

1

minute

exercising

table.

mechanism

Learning

the

end

outcomes

of

this

topic

you

breathing

mechanism

of

b

his

the

ensures

t hat

t he

air

in

t he

alveoli

is

refreshed

gases

in

t he

lungs

continues

be

able

to:

so ●

t hat

patterns

a

minute.

should

The

athlete;

breath

By

of

breathing

minute

during

exercise.

breathing

Mechanism

The

male

table:

the

of

old

exercise. while

Include

B.2.1.12

16-year

describe

the

breathing

efciently.

mechanism

Movement

high

of

pressure

air

during

region

to

breathing

a

low

depends

pressure

on

region.

the

Air

fact

is

that

air

breathed

moves

in

from

a

●

outline

the

when

than

our

chests

expand.

atmospheric

This

pressure

so

makes

that

the

air

is

pressure

pushed

of

by

air

the

inside

higher

the

our

lungs

pressure

less

●

rate

explain

of

lungs.

This

so

Air

makes

that

is

the

some

of

breathed

pressure

the

air

out

(expiration)

inside

is

our

pushed

chests

out

by

when

we

greater

the

compress

than

higher

affecting

our

breathing

rescue

breathing

into (artificial

our

factors

(inspiration)

resuscitation).

chests.

atmospheric

pressure

pressure.

Inspiration

During

inspiration

backbone,

par t

made

t he

of

t he

lower

tough

muscles

ribs

and

brous

of

t he

t he

diaphragm

sternum

tissue.

The

t hat

contract

external

connect

and

atten

intercostal

to

t he

t he

muscles

central

contract

103

835292

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HSB

Unit

B

Topic

2.indd

103

08/01/2015

16:05

The

breathing

The

mechanism

and

t he

internal

outwards.

These

decreasing

is

greater

air ways

During

●

t he

t han

air

pressure

t he

inating

muscles

air

t he

relax.

increase

inside

pressure

t he

of

The

t he

ribcage

volume

lungs.

inside

Now

lungs,

moves

inside

t he

so

exchange)

t he

upwards

chest

moves

into

and

(t horax),

atmospheric

air

system

pressure

t he

lungs.

external

muscles

contract

intercostal

muscles

to

move

contract

passage passage

t he

(gas

inspiration:

diaphragm

●

intercostal

movements

respiratory

of

t he

to

diaphragm

move

t he

down

ribcage

up

and

out.

air

air

trachea trachea

external

external

intercostal

intercostal

muscles muscles

relax

contract

ribs

move

and

out

up

ribs

move

and

in

down

lungs

lungs

ribcage ribcage

diaphragm

the

volume

the

chest

the

volume

the

chest

of

of

cavity

cavity

diaphragm

decreases increases

contracts

and

diaphragm

relaxes

and

diaphragm

moves

upwards

down

front front

p

view

Figure

during

rib

cage

up

chest

side

B.2.2.1(a)

breathing

Movement

of

the

of

rib

cage

and

down

moves

diaphragm

diaphragm

thorax

volume

increases

and

the

ribcage

down

moves

view

of

chest

p

Figure

B.2.2.1(b)

breathing

Movement

of

the

diaphragm

and

the

ribcage

out

up

of

thorax

t he

expiration

abdomen

shape.

The

t he

diaphragm

pushes

internal

t he

muscles

central

intercostal

relax

brous

muscles

and

tissue

contract

t he

pressure

upwards

and

t he

into

a

exer ted

dome

external

decreases

These

of

side

Expiration

intercostal

volume

chest

inwards

by

of

of

chest

During

volume

view

during

out

moves

view

in

moves

and

diaphragm

of

bulges

lungs

volume

increases

of

lungs

muscles

movements

pressure

inside

relax

so

decrease

t he

lungs.

t he

t he

The

ribcage

moves

volume

inside

elastic

tissue

downwards

t he

t horax,

around

t he

and

inwards.

increasing

alveoli

recoils

t he

air

and

decreases

t his

helps

to

force

air

out

of

t he

lungs.

Note that the diaphragm muscles and intercostal muscles are used together air

pressure

in

lungs

air

decreases

pressure

in

lungs

when you breathe in and out. Sometimes when breathing with shallow breaths

increases

you can just use your diaphragm and the intercostal muscles are not used at all.

The air

flows

into

the

breathing

p

Figure

lungs

air

IN

flows

out

of

breathing

B.2.2.2

Flow

charts

the

breathing

Tr y

OUT

happens

breathing

during

breathing

out

is

summarised

in

the

ow

charts

in

Figure

B.2.2.2.

this

yourself

showing

Making what

mechanism

lungs

in

a

model

of

the

breathing

mechanism

and

Requirements

●

2

balloons

●

a

clear

●

a

pair

1

Cut

the

plastic

of

off

for

a

one-lung

water

model

bottle

(without

cap)

●

a

thumbtack

●

sticky

tape

or

masking

tape

scissors

the

balloon

part

is

of

the

going

to

balloon

be

the

with

the

hole

diaphragm

in

for

blowing

your

into.

The

rest

of

model.

104

835292

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HSB

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Topic

2.indd

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The

respiratory

2

Use

of

3

the

the

the

in

exchange)

thumbtack

water

Cover

stays

(gas

to

system

make

a

The

small

hole

about

3

mm

wide

in

the

breathing

mechanism

bottom

bottle.

bottom

place

of

you

the

can

water

fix

it

bottle

with

with

the

balloon.

T o

make

sure

it

tape. balloon

4

Put

the

around

the

of

second

the

top.

the

rim

Y ou

balloon

of

can

the

use

inside

bottle

more

the

so

bottle.

the

sticky

Fold

balloon

tape

to

the

hangs

hold

top

of

into

the

the

the

balloon

bottle

balloon

onto

from

the

rim

bottle.

plastic

5

Now

use

your

model

to

show

what

happens

to

the

lungs

during

drinks

breathing bottle

in

6

and

breathing

Match

a

the

Which

out.

structures

parts

between

are

the

of

your

respiratory

represented

bottle

and

the

by:

the

system

bottle,

balloon,

the

to

the

the

parts

balloon,

of

the

the

model.

space

balloon

diaphragm?

cut

b

Which

c

What

in

7

Use

T ake

some

we

Y ou

can

some

respiratory

with

your

system

model

as

a

are

not

way

of

represented

in

demonstrating

the

the

make

and

to

teach

a

artist

two-lung

tubing.

be

to

to

The

secured

someone

show

draw

by

model

an

air

how

for

plastic

else

in

a

tubing

tight

your

much

us

with

in

better

Figure

Y -

or

a

must

seal.

family

your

how

we

model

breathing

p

Figure

brain

brain

of

exercise

detects

each

changes

of

t he

time

integrates

determines

inuences

●

A

one-lung

model

to

breathe

is

than

the

B.2.2.3.

T -shaped

t

inside

Modelling

connector

the

clay

opening

could

be

and

of

the

used

on

in

blood

breathing

t he

and

oxygen

t he

and

extent

carbon

to

which

t he

Study

✔

dioxide

you

breat he

in

and

out.

The

lungs

breat hing

t he

our

in

an

an

increase

increase

increase

t he

information

and

rate

of

from

inside

breat hing.

and

outside

Exercise

is

one

t he

body

factor

effects

in

in

in

of

exercise

breat hing

t he

dept h

t he

on

breat hing

and

t hat

minute

information

make

happens

a

table

to

breathing

in

this

in

the

showing

following

and

chapter

what

during

breathing

●

diaphragm

●

intercostal

●

ribcage

●

volume

of

thorax

●

volume

of

lungs

●

air

●

movement

out:

muscles

are:

rate

of

the

t he

breat hing.

shor t-term

an

all

dept h

tip

are

centre

to

●

we

breathe.

Use

stretched

●

B.2.2.3

how

this.

concentrations

The

top

model?

show

photographs

asked

Effects

The

the

wrong

model

plastic

bottle

for

is

of

humans?

the

one

parts

with

off

breat hing

volume

(volume

of

air

breat hed

in

during

pressure

in

the

lungs

a of

air

in

the

airways

minute)

●

an

increase

Regular

exercise

physiology.

●

●

●

in

t he

also

These

an

increase

an

expansion

an

increase

diaphragm

in

in

amount

has

of

carbon

long-term

dioxide

benecial

in

expired

effects

on

air.

t he

body’s

include:

t he

of

number

t he

size

of

capillaries

in

t he

lungs

alveoli

and

strengt h

of

t he

intercostal

muscles

and

muscles.

105

835292

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Unit

B

Topic

2.indd

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16:05

The

breathing

The

mechanism

Other

factors

that

affect

respiratory

(gas

exchange)

system

breathing

Drugs

Some

dr ugs,

breat hing.

e.g.

amphetamines,

Ot hers

are

are

depressants

stimulants

and

have

and

t he

speed

opposite

up

t he

rate

of

effect.

Anxiety

If

we

are

frightened

increase

needs

our

to

be

adrenaline

removed.

and

t his

Environmental

You

may

and

t here

increase

brain

to

have

is

in

or

breat hing

worried

as

about

more

This

is

because

increases

somet hing,

oxygen

t he

is

needed

when

rate

of

t hen

and

anxious

t his

is

more

we

likely

carbon

tend

to

to

dioxide

secrete

more

respiration.

factors

noticed

little

carbon

increase

t hat

if

you

ventilation

dioxide

t he

are

t hat

in

you

a

small

star t

concentrations

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106

835292

CSEC

HSB

Unit

B

Topic

2.indd

106

08/01/2015

16:05

The

respiratory

(gas

exchange)

1

Lift

the

Pinch

the

hand,

lower

This

the

the

the

The

nostrils

shut

with

the

fingers

breathing

mechanism

of

chin one

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system

will

air

then

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tilt

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forward

force

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head

so

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the

tongue

chin

and

juts

forward

push

out.

and

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head

backward

2

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a

deep

mouth

against

the

breath,

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person’s

then

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open

lips

mouth.

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out

firmly

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the

person’s

your

mouth

to

look

into

the

at

off,

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person’s

turn

your

chest.

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head

you

so

have

successful

you

will

see

that

it

has

risen

lungs.

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4

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now

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Figure

B.2.2.4

Step

1:

Lie

t he

Step

2:

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one

gently

steps

t he

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as

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Step 3: Push the chin up to lift the tongue and search for and remove any

debris (including false teeth) in the mouth.

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4:

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t he

nostrils

of

t he

injured

person,

take

a

deep

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p

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chest

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your

lips

and

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out

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is

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to

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rescue

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5:

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6:

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twice.

t hat

indicates

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7:

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for

for

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8:

signs

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of

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position

of

of

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rate

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person

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and

per

minute

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swallowing,

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movement,

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minute)

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check

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breat hs

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put

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is

essential

t hat

an

ambulance

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medical

help

are

B.2.2.6

into

the

The

person

recovery

should

position

be

when

called. they

are

breathing

normally

107

835292

CSEC

HSB

Unit

B

Topic

2.indd

107

08/01/2015

16:05

The

Smoking

respiratory

(gas

exchange)

system

Questions

1

The

diaphragm

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the

forced

2

a

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5500

3

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4

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the

end

should

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be

of

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able

outline

why

topic

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of

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volume

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b

you

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other

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than

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used

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muscles

thorax?

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of

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altitude,

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that

biological

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at

difficult

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at

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pressure

oxygen

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gentle

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diaphragm.

concentration

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aid

of

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against

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factors,

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constituents

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the

up

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will

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altitude

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pushing

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altitude.

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of

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volunteers?

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to:

the

would

B.2.3

outcomes

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organs

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five

group

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to:

intercostal

expiration,

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happen

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nicotine

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over

4000

substances

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it.

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impor tant

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t he

dr ug

in

tobacco

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absorbed

into

t he

blood

addictive ●

●

explain

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damage

carbon

monoxide

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gas

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substances

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●

explain

causes

the

monoxide

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the

the

of

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●

carbon

tar

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●

black

the

effects

on

carcinogens

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present

graphs

data

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to

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carbon

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B.2.3.1

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adverse

effects

on

health

people

are

widely

people

smoke

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a

choose

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to

the

right

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to

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a

on

into

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is

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one

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of

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healt h

of

people

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and

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t hat

addictive

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body

also

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of ten

we

is

wit h

t he

it

people

cardiovascular

t hen

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t hroughout

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one

as

are

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cells

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makes

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body

ner ve

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plant

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interacts

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effects

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to

t he

in

by

carbon

by

up

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haemoglobin.

monoxide.

10%.

circulator y

air ways

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nd

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system

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also

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volume

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hear t

of

oxygen

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oxygen

disease

t hat

and

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system.

many

settles

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reduces

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on

compounds

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from

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at

tar.

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it

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trachea

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eventually

destroys

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cilia

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line

much

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and

gas

known

exchange still

up.

in

substance

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in smoking

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a

monoxide

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in

present

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nicotine,

herbivores.

vessels).

permanently

ar teries

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by

stimulant

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it

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Figure

it

effect.

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eaten

physiology.

and

but

–

leaves

being

smoked,

as

our

p

oily

oxygen

outline

of

a

transport ●

of

–

system

(see

page

97).

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protect

our

lungs

by

carr ying

mucus,

smoke.

decision

to

wit h

it

is

trapped

t he

site

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bacteria,

from

t he

air

passages

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t he

t hroat,

where

swallowed.

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dust

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for

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cells

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leads

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in

mucus

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destr uction

to

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formation

of

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cilia

becomes

t he

a

continual

tissue

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to

move

good

irritation

Figure

it

out

breeding

of

t he

B.2.3.2).

108

835292

CSEC

HSB

Unit

B

Topic

2.indd

108

08/01/2015

16:05

The

respiratory

(gas

exchange)

system

a

Smoking

b

ciliated

cilia

cells

mucus

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along

dust

these

particles

make

cells

✔

mucus

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is

about

drugs

use

tip

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nicotine

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in

Unit

as

an

information

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example

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of

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stimulant.

p

Figure

B.2.3.2

airways,

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and

smokers

developing

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become

alveoli.

lining

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t he

alveoli

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cannot

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t he

bronchi.

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genes

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to

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in

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break

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enter

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t he

cells

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cells

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and

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p

this

B.2.3.3

cancer

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burst,

smoke

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remove

enter

t he

DNA

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carbon

bronchitis

wit h

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area

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of

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t he

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tumour

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treat

scientists

lung

to

a

sur pr isingly

cancer.

r ise,

e.g.

Indeed,

in

t he

UK

long

when

in

t he

time

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to

realise

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1930s

and

of

t hat

cases

1940s,

cigarette

of

lung

cigarette

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cancer

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Figure

B.2.3.4

cancer

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or

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team

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as

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cause!

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grown

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graph

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cell.

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109

835292

CSEC

HSB

Unit

B

Topic

2.indd

109

08/01/2015

16:05

The

Smoking

Figure

B.2.3.6

1910

to

from

lung

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tobacco

and

its

impact

on

your

health

from

every

country

in

the

world.

T able

B.2.3.1

shows

selected

is

data

13

countries

including

some

from

the

Caribbean

as

published

in

the

2012

at of

the

T obacco

Atlas.

The

table

shows:

time.

is

occur

period,

high

people

population

edition

the

very

year.

for

with

a

week,

collected

Prevalence

for

a

own

per

smoking

cases

spreadsheet

specic

on

expressed

This

of

skills

tip

the

number

over

e.g.

per

a

of

deaths

particular

week,

time

month

or

●

the

number

●

the

percentage

year .

of

cigarettes

smoked

per

of

the

adult

male

adult

female

person

population

per

who

year

smoke

(prevalence

of

smoking)

●

the

percentage

of

the

●

the

percentage

of

deaths

as

a

population

result

of

who

smoking

in

smoke

males

and

females

110

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The

q

respiratory

T able

(gas

exchange)

system

Smoking

B.2.3.1

Country

Cigarettes

Male

Female

Male

Female

per

person

prevalence/%

prevalence/%

deaths/%

deaths/%

per

year

Barbados

Bulgaria

344

15

2

4

0

2822

50

28

22

5

809

23

16

23

20

Canada

Cuba

1261

31

16

21

18

Czech

2125

43

30

26

10

339

12

3

9

13

Republic

Dominica

p

Figure

taking Guyana

49

29

3

3

283

23

8

12

6

1841

38

11

22

12

539

46

2

22

15

1106

30

21

10

1

Jamaica

Japan

B.2.3.7

risks

This

with

9-year-old

his

boy

is

health

1

Did

you

know?

? Malaysia

In Trinidad

and

2014,

was

T obago

of UK

750

22

21

22

1028

31

23

US$23.6

23

who

the

Present

the

countries

lowest

data

from

on

cigarette

T able

cigarette

B.2.3.1,

consumption

including

the

as

a

bar

chart

by

with

the

countries

to

Is

there

of

any

deaths

against

3

Is

4

Discuss

5

Suggest

linked

to

between

smoking?

of

deaths

correlation

smoking?

the

other

smoking,

cigarette

Plot

in

the

data

the

data

from

disease

in

of

to

find

in

1996

of

of

a

lung

choosing

highest

six

and

Her

informing

of

lawyers

company

was

people

consuming

argued

that

negligent

of

the

in

dangers

tobacco.

death

the

of

to

percentage

consumption

find

out.

smoking

and

July

2014.

from

BBC

News

20th

http://www.bbc.co.uk/

news/world-us-canada-28389273

deaths

out.

in

countries

early

and

cigarette

females

presented

these

and

and

prevalence

scattergraphs

of

consumption

scattergraphs

males

between

Plot

limitations

what

between

Case

correlation

any

to

damages

widow

consumption.

percentage

there

linked

company

pay

the

died

[Information

2

to

23

cancer.

1

tobacco

20

man USA

a

ordered

the

table.

would

much

make

the

link

clearer.

study

Evidence

for

the

link

between

smoking

and

lung

cancer

53

100

a

page

what

famous

109).

might

doctors

habits

Toget her

to

was

take

British

of

In

he

par t

in

obtained

his

t he

in

disease.

information

1951,

and

of

epidemiologist

collected

it.

patterns

he

began

researchers

study.

1951

a

and

who

on

worked

lung

recr uited

inter vals

in

cancer

long-term

Information

at

Professor

nd

of

34 439

about

Richard

Oxford

to

study

t heir

t hereaf ter

Sir

out

British

male

British

smoking

until

t he

study

egatnecrep

doctors.

He

cause

study

lavivrus

(see

was

t he

80

morf

Doll

is

ega

Epidemiology

60

cigarette

smokers

40

20

0

was

ended

in

2001.

When

each

doctor

died,

t he

researchers

recorded 40

50

60

70

80

90

100

age / years

t he

cause

smokers

of

deat h.

were

The

cancer,

most

common

respirator y

causes

diseases

and

of

deat h

hear t

among

t he

disease. p

Figure

B.2.3.8

doctors

Figure

B.2.3.8

shows

t he

sur vival

of

smokers

and

non-smokers

doctors

who

were

50

or

younger

when

t he

study

The

survival

between

of

1900

male

and

among

1930

t he

bor n

–

some

of

the

results

from

the

star ted. British

Doctors

Study

111

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Cell

The

respiration

respiratory

(gas

exchange)

system

Questions

Talk

about

? 1

Ban

Why

smoking!

Consider

the

of

following:

2

do

t his

you

t hink

long-term

Professor

Doll

chose

male

doctors

as

t he

subjects

study?

Use the information in Figure B.2.3.8 to state the percentage of male

British doctors who had died by the age of 70 in each of the two groups. Over

●

die

90%

from

the

lung

smoked

●

of

people

cancer

who

have

3

Describe

cigarettes.

Up

to

50%

die

early

of

t he

smokers

trends

shown

in

t he

results

of

t his

study

numbers

of

cases

as

shown

in

graph.

may

4 from

t he

In

many

in

females

par ts

of

t he

world

t he

of

lung

cancer

smoking-related

has

risen

shar ply

in

recent

years.

Suggest

why

t his

has

diseases.

happened. Smokers

●

die

in

are

more

middle

age

likely

than

to

non-

5

Suggest

smokers.

T obacco

●

than

5

use

causes

million

The

deaths

by

per

a

is

the

costs

smoking

time

complete

smoking

your

to

tobacco.

of

ill

are

1

Name

and

on

two

this

2

State

the

end

3

Suggest

of

this

able

explain

define

topic

the

role

of

than

lung

cancer,

which

are

associated

with

pieces

of

evidence

that

link

smoking

to

lung

cancer.

some

and

people

have

lower

vital

capacities

than

predicted

by

height.

Cell

respiration

heat.

is

the

Energy

breakdown

was

dened

of

on

food

page

to

release

20

as

the

energy

ability

in

to

t he

do

form

work.

of

ATP

Examples

ATP

between

anaerobic

cells

in

our

bodies

doing

the

work

enzymes

are

to

and

applications

and

all

cells

energy

to

do

t his

work

lose

a

triphosphate

muscle

cells

taking

comes

phosphate

(ATP).

group

and

cells

contracting,

engulng

bacteria,

ner ve

cells

pancreas

up

ions

by

active

cells

transpor t.

from

This

a

chemical

releases

form

its

present

adenosine

energy

in

when

all

it

cells,

breaks

down

diphosphate:

of

adenosine

anaerobic

blood

of

adenosine

industrial

domestic

white

respiration

concept

debt

describe

impulses,

aerobic

The explain

oxygen

●

other

respiration

distinguish

and

t he

you

making

●

diseases,

why

age

transmitting

●

reduce

to:

of

●

to

Caribbean.

outcomes

and

●

attempt

t he

smoking.

two

Respiration be

can

in

with

B.2.4

should

cancer

teachers.

their

By

lung

health

huge.

ban

Discuss

family

Learning

governments

of

introduce

worldwide

friends,

which

cases

year

cigarette Now

in

new

Questions

economic

caused

of

more

worldwide.

●

ways

number

adenosine

respiration.

triphosphate

(ATP)

diphosphate

(ADP)

+

phosphate

(P

)

+

energy

i

All

cells

stay

Key

in

all

Cell respiration

chemical

breakdown

(carbohydrate,

using

oxygen

form

and

of

of

protein

to

ATP

nutrients

and

release

and

cells

–

it

breakdown

●

fat)

energy

breakdown

stored

respiration

of

oxygen

form

using

of

supply

out

of

t heir

ATP

in

various

t heir

cells

functions.

if

t hey

ATP

is

are

t he

to

continue

‘energy

to

nutrients

to

ATP

release

and

t he

is

form

t he

in

which

process

by

all

energy

which

t his

transactions

ATP

is

made.

are

currency’

It

conducted.

involves

t he:

in

of

t heir

nutrients

(mainly

glucose

and

lipid)

to

release

t he

energy

molecules

in

use

of

some

of

t his

energy

to

rebuild

ATP

from

ADP

and

phosphate:

heat.

+

phosphate

energy

(p

)

+

energy

from

nutrients

ATP

i

without

heat

diphosphate

The

●

loss

of

t he

rest

of

t he

energy

as

heat.

in

There the

carr y

is

respiration

adenosine Anaerobic

using

a

The

●

the

alive

have

terms

!

Aerobic

must

are

two

types

of

respiration:

aerobic

respiration

and

anaerobic

without

respiration

oxygen.

112

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The

respiratory

Aerobic

(gas

exchange)

system

Cell

respiration

respiration

ADP

Energy +

In

t his

process

t he

breakdown

of

nutrients

(glucose

and

lipids)

Pi

involves

for

cell

e.g.

t he

use

of

oxygen.

Carbon

dioxide

and

water

are

always

produced

as

activities,

movement,

waste making

products

and

energy

to

rebuild

ATP

is

released.

The

most

commonly

active

substrate,

Aerobic

and

t he

only

respiration

of

one

t hat

glucose

cells

can

in

be

our

brains

represented

can

by

use,

t he

is

protein,

used transport

glucose.

word

equation:

ATP

glucose

+

oxygen

carbon

dioxide

+

water

+

energy

energy

Aerobic

respiration

occurs

inside

t he

mitochondria

of

our

cells

(see

used

B.2.4.2

by

a

and

B.2.4.3)

molecule

of

and

releases

glucose

in

a

great

aerobic

deal

of

respiration

energy.

is

The

enough

energy

to

released

rebuild

up

Pi

30

molecules

of

ATP

from

ADP

and

to

during

cells.

ATP

Cristae

is

and

sausage-shaped

infoldings

of

Figure

B.2.4.1

recycles

organelles

t he

inner

found

in

membrane

t he

of

cytoplasm

t his

organelle

for

respiration

t hat

cells

do

not

receive

enough

oxygen

for

all

t he

t hey

want

to

do.

For tunately,

t his

does

not

respiration

back

slows

down

or

stops.

Cells

can

still

carr y

out

many

chemical

reactions

mitochondria

absence

t his

of

because

oxygen

process

cannot

respire

anaerobic

respire

bacteria

Instead

of

anaerobic

acid

of

respiration

is

t he

fat

t he

wit h

lack

breakdown

by

to

provide

activities

but

t hey

are

unable

to

oxygen.

when

of

respiration,

as

in

a

glucose

This

does

respiration,

make

many

and

e.g.

produced

oxygen.

greater

We

making

dioxide

a

of

form

to

of

use

lactic

acid

is

or

of

not

only

lesser

use

fungi

and

in

plants,

respiration

in

remind

energy.

write

about

respiration

occurs

in

cells

make

process

sure

to

the

role

of

you

ATP .

t he

involve

glucose.

extent;

oxygen.

All

some

anaerobic

We

organisms

can

microorganisms

respiration

in

yeasts

ot her

bacteria

and

waste

in

products

animals

are

produced

(including

in

humans),

product:

lactic

acid

+

energy

known

as

Figure

B.2.4.2

micrograph

lactate.)

et hanol

and

carbon

dioxide

are

produced

as

added

products:

are

glucose

to

and

energy-consuming

of

An

a

mitochondrion.

waste

A.2

cells

products.

water,

waste

also

Unit

t heir

p

t hat

to

respiration.

anaerobic

respiration

carbon

is

of

anaerobic

glucose

In

cell’s

of

refer

●

continually

A TP

tip

about

you

any

that

(Note

the

into

mean

or

lactic

all

Pi

aerobic

When

and

Respiration

and

Exam

yourself

never

ADP

where

Look

our

use

and

and

respiration

Sometimes

In

ADP

made.

Anaerobic

t he

released

of

✔

t hat

is

from

respiration

energy

are

ATP

P i

Mitochondria

glucose

make

to p

about

from

Figures

et hanol

+

carbon

dioxide

+

to

not

this

red

electron

section

Colour

image

and

–

blue

through

has

a

been

mitochondria

(x 20

000)

energy

cristae

The

waste

substances

substances.

molecules.

from

t he

aerobic

lactic

Anaerobic

Only

two

anaerobic

acid

respiration

molecules

respiration

respiration.

and

When

is

of

of

et hanol

wasteful

ATP

are

glucose.

sprinters

r un

are

of

t he

made

That

t he

still

energy

wit h

is

100

energy-rich

15

t he

times

metres

in

glucose

energy

less

t heir

released

t han

hear t

in

and

matrix

lungs

cannot

respiration

get

so

enough

t hey

have

oxygen

to

use

to

t heir

anaerobic

muscles

to

maintain

respiration

instead.

aerobic

This

uses

lots inner

of

glucose

molecules

to

generate

t he

ATP

t hat

t hey

need.

Their

training

outer

designed

to

have

energy

lots

make

sure

t hat

stored

as

by

t he

time

glycogen

t he

star ter

because

so

gun

much

goes

of

t he

t heir

t he

lactic

acid

t hey

membrane

muscles

energy

is

wasted p

in

membrane

is

Figure

B.2.4.3

Compare

the

structure

produce. of

the

with

mitochondrion

this

in

Figure

B.2.4.2

diagram

113

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The

respiration

q

Study

✔

T able

B.2.4.1

Comparison

of

aerobic

and

respiratory

anaerobic

(gas

respiration

in

of

is

an

opportunity

maths

skills.

actual

size

Figure

B.2.4.2?

of

the

to

What

Anaerobic

practise

is

the

Is

mitochondrion

oxygen

required?

Yes

No

in

How

per

much

energy

molecule

What

are

of

the

is

released

A

lot

A

Does

you

it

end

occur

little

glucose?

products?

CO

and

H

2

Did

animals

respiration

Aerobic

your

system

tip T ype

Here

exchange)

in

mitochondria?

O

Lactic

acid

2

Yes

No

know?

?

Mitochondria

lead

a

semi-

Oxygen independent

They

the

take

rest

A TP

in

in

of

life

from

cell

return.

your

and

Y ou

from

your

fertilised

in

to

the

egg

become

Humans

back

dur ing

your

mother

are

cells

as

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produced

cell

that

shor t

of

key

much

glucose

waste

t here

is

oxygen,

energy

here

is

an

oxygen

an

the

Lactic

diffuses

acid

to

t he

acid

you

start

lactic

builds

we

die.

However,

to

active

muscle

anaerobically.

Lactic

acid

up

in

t he

muscle

cells

t hat

is

muscle

fatigue

and

soreness.

Dur ing

are

t his

because

soon

oxygen

is

going

to

be

time

needed

to

hear t

acid.

out

and

of

t he

per

a e ro b i c a l ly.

fo r

p rov i d e

molecule

end

of

all

respiration.

of

sto ra g e

t he

lactic

Fi g u re

muscle

l i ve r.

cells

Hear t

i n to

t he

muscle

blood

uses

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car r ied

to

of

and

the

as

difference

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exercise

decit

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we

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cells

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and

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re s p i re

t he

of

t he

re st

lactic

re s p i re

acid

a e ro b i c a l ly

i n to

to

build

cannot

to

acid

wit h

e n e r g y.

re s p i re

has

lactic

been

The

acid

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re m ove d ,

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called

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up

t he

ox yg e n

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is

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debt

has

debt.

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at

t he

Once

re p a i d

B.2.4.4).

ideal

know

as

t h e m s e lve s

e xe rc i s e

tip

decit

oxygen

respire

oxygen

delivered

deficit

and

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–

real

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oxygen

between

an

update

oxygen

negyxO

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and

be

ekatpu

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oxygen

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product

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✔

so

oxygen

you.

respiration

than

enough

a

aerobically:

tip

message

less

as

respire

exercise,

was

gl u c o s e

anaerobic

to

descended

lactic

The

have

vigorous

quic kly

away

✔

debt

cells.

from

give

inherited

mitochondria

those

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compounds

the

mitochondria

all

inside

that

debt

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–

needed

extra

to

oxygen

convert

acid resting

get oxygen

enough

result

oxygen

we

have

anaerobic

debt

is

into

lots

our

of

lactic

respiration.

the

volume

of

bodies.

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acid

As

a

uptake

from

oxygen

oxygen

that before

needs

to

respire

be

the

‘repaid’

lactic

after

exercise

to

Study

tip

Figure

carefully

at

the

graph.

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is

much

the

the

curve

oxygen

that

was

shows

taken

make

up

exercise

Oxygen

uses

much

use

uptake

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of

into

the

body

anaerobic

t he

products

of

before,

during

and

after

strenuous

exercise

respiration

anaerobic

respiration

in

yeast

and

We

use

t hese

microorganisms

in

many

industrial

and

domestic

how

by

processes,

also

athlete.

after

red

bacteria. line

B.2.4.4

Economic

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exercise

Time

acid.

p

✔

during

exercise

in

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providing

is

a

and

respire

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for

t he

making

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aerobically

cells

only

such

fungus

yeast

as

initial

page

When

anaerobically

has

such

breaking

(see

anaerobically.

glucose

substances

access

to

to

9)

down

t hat

t here

for m

as

is

a

beer

our

can

oxygen

so

yoghur t,

but

wastes.

respire

lac k

et hanol

and

of

and

t hat

bot h

oxygen,

it

carbon

respires

yeast

dioxide.

aerobically,

114

835292

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HSB

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B

Topic

2.indd

114

08/01/2015

16:05

The

respiratory

produces

t hen

t hat

and

a

lot

of

decreases

is

exchange)

ATP

and

required.

it

For

and

system

t herefore

st ar ts

divides

respir ing

centur ies

Cell

rapidly.

anaerobically

humans

have

The

to

oxygen

produce

exploited

yeast

in

respiration

supply

t he

product

brewing

breadmaking.

Many

bacter ia

decreases

of

(gas

milk .

t he

It

pH

might

organisms

do

refr igeration

most

also

of

t he

seem

not

and

common

respire

wit hout

sur roundings

strange

g row

oxygen

well,

freezing,

met hods

to

if

at

all,

sour ing

of

food

and

make

to

has

milk

in

and

produce

acid

been

go

preser vation.

used

sour,

pH.

salting

In

lactic

but

t he

foods

Think

in

t he

food

days

were

of

acid.

This

sour ing

spoilage

before

two

of

yoghur t

t he

and p

salted

cod

Figure

B.2.4.5

These

sprinters

rely

sh. on

anaerobic

respiration

in

their

leg

muscles

Today

fermentation

domestic

yeast

and

bacteria

Domestic

Many

uses

foods

respiration

make

(see

beer,

Tr y

is

used

consumption.

mass

home

are

also

produce

beverages

and

wine

yourself

uses

t he

to

produce

industries

a

range

large

and

of

foods

small

for

t hat

use

foods.

fermentation

yeasts

home

this

Industrial

of

and

of

to

in

There

on

be

made

in

bacteria,

can

some

examples

making,

pages

bread

t he

making

home

using

are

and

t he

home

yoghur t

anaerobic

brewing

to

making

1 16–17).

of

fermentation

of

beer

Brewing p

The

in

production

Guyana

brewing

into

is

is

t hen

respires

t he

This

Hot

and

t he

t he

is

spent

group

is

widely

Red

to

in

Stripe

t he

in

germinated

used

added

glucose

t he

B

is

and

grain

water

yeast

process,

especially

Barbados

grain.

maltose.

cooled

of

and

occurs

to

to

it.

Yeast

form

yeast

extract

be

Jamaica.

so

t he

and

breaks

et hanol

can

Caribbean,

seeds

dissolve

down

and

eaten,

The

it

is

a

raw

Banks

breakdown

t he

to

for

and

t his

glucose

and

At

source

Figure

B2.4.6

These

runners

(5000

aerobic

respiration

long

metres)

in

distance

depend

their

leg

on

muscles

starch

maltose

dioxide.

rich

Beer

material

maltose

carbon

as

e.g.

t he

of

end

vitamins,

vitamins.

Breadmaking

Dough

will

is

produced

allow

dioxide.

causes

it

et hanol

t he

The

to

yeast

by

to

carbon

rise.

dioxide

When

t he

our,

down

causes

dough

water,

t he

is

sugar

sugar,

t he

dough

baked,

and

yeast.

producing

t he

to

increase

yeast

Gentle

et hanol

cells

in

die

warming

and

volume

and

carbon

t hat

t he

evaporates.

Practical

Rising

mixing

break

Activity

dough

p

Figure

B.2.4.7

Mauby,

which

is

made

Requirements from

●

stirring

●

measuring

jug

●

measuring

cylinder,

●

thermometer,

●

timer

●

laboratory

fermented

bark

rod

3

e.g.

e.g.

50

cm

0–100°C

balance

115

835292

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HSB

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B

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2.indd

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08/01/2015

16:05

Cell

The

respiration

●

water

●

plain

●

dried

baths

set

at

a

variety

of

respiratory

temperatures,

(gas

exchange)

including

system

40°C

flour

yeast

made

into

a

yeast

suspension

(add

7

g

dried

yeast

to

3

450

warm

water

and

stir)

sugar

●

1

cm

Add

25

add

1

g

g

of

of

flour

to

a

measuring

jug

or

other

to

the

suitable

container

and

then

sugar.

3

2

Add

30

cm

have

made

Pour

the

of

a

the

yeast

smooth

suspension

paste

that

can

be

flour

and

sugar.

Stir

until

you

poured.

3

3

to p

Figure

for

B.2.4.8

industrial

Fermenting

alcohol

sugar

let

paste

the

into

paste

a

50

touch

cm

the

measuring

sides

–

this

cylinder

is

very

and

take

great

care

not

important.

cane

production

4

Note

the

water

2

volume

baths.

minutes

for

Repeat

steps

6

Record

your

7

Plot

Y ou

of

can

more

use

plot

the

the

for

the

than

Describe

b

Explain

c

Suggest

should

of

if

the

the

Suggest

a

cylinder.

different

Place

and

note

the

the

cylinder

volume

in

of

one

of

paste

the

every

temperature

each

time.

table.

the

for

they

volume

the

are

on

of

different

the

the

separate

allows

graphs.

and

Alternatively,

dough

increases

temperatures

results

spreadsheet

graph.

print

use

you

It

is

them

the

on

to

the

graph

for

time.

same

compare

quicker,

out

with

pair

them

however,

everyone

drawing

to

to

facility

of

program.

effect

effect

suitable

be

the

presenting

on

the

spreadsheet

a

a

how

results

way

plotting

in

show

in

temperature

minutes.

using

results

a

d

to

This

easily

collect

1– 4

the

30

results

graph

axes.

paste

about

5

a

of

Record

of

of

different

temperatures

temperature

controls

for

this

on

the

on

rising

the

of

investigation

dough.

dough.

and

explain

why

they

included.

ways

to

improve

the

investigation.

Yoghurt

Bacteria,

They

t he

such

ferment

protein,

yoghur t

is

Making

Lactobacillus

lactose

lowers

not

avourings

Tr y

as

t he

to

and

this

t he

and

sugar

pH

and

ever yone’s

in

Streptococcus

milk

gives

taste

so

to

t he

give

are

used

lactic

yoghur t

a

sour

manufacturers

to

acid,

add

make

which

taste.

such

yoghur t.

coagulates

Natural

t hings

as

fr uit.

yourself

yoghurt

Requirements

p

Figure

B.2.4.9

Homemade

yoghurt

●

any

●

spoon

type

●

stirring

●

measuring

●

sterilised

●

pot

of

of

milk

rod

jug

container,

live

yoghurt

glass

(check

jar

or

the

plastic

label

to

cup

make

sure

it

contains

live

bacteria)

116

835292

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2.indd

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08/01/2015

16:05

The

respiratory

●

a

●

foil

1

Heat

(gas

exchange)

system

Cell

respiration

thermometer

or

cling

wrap

some

milk

in

a

saucepan

to

about

75°C.

Allow

to

cool

to

room

temperature.

3

2

Pour

50

cm

into

a

sterilised

container.

3

3

Add

1

cm

4

Cover

the

5

Place

to

6

6

If

the

hours

you

a

do

and

try

in

a

not

of

the

with

different

live

ingredients

things

to

add

a

What

b

Research

of

is

it

doesn’t

is

the

if

different

yoghurts

almost

to

as

hygiene

of

it

hourly

and

fruit,

intervals.

keep

this

of

the

precautions

in

milk,

a

school

even

at

In

order

42– 43°C

for

of

you

milk

adding

the

nuts,

milk.

eat

the

and

coconut

live

yoghurt;

the

bacteria;

seeds,

may

lab.

goat’s

before

source

–

thoroughly.

37.7°C.

powder

the

at

try

appearance

make

types

yoghurts

Try

adding

oatmeal.

The

range

endless.

nutritional

online

the

milk

but

wrap.

below

you

gently

observe

drop

in

stir

should

suitable

product

your

and

you

changes

with

and

cling

place

skimmed

to

milk

or

bacteria,

any

some

the

foil

warm

kitchen

eat

adding

using

a

ensure

record

Do

different

of

in

to

with

cultivate

experimenting

milk;

try

milk

this

product.

yoghurt

container

properly

Keep

Try

live

value

find

out

of

yoghurt?

what

food

additives

are

in

different

brands

yoghurt.

c

What

are

d

Design

these

an

additives

investigation

for?

to

find

the

best

temperature

to

use

for

of

star ter

making

yoghurt.

Case

study

Acidophilus

The

yoghurts

production

cultures

of

two

of

all

yoghur ts

bacteria:

star ts

wit h

Lactobacillus

t he

addition

bulgar icus

and

✔

Study

tip

Streptococcus Microorganisms

thermophilus.

If

a

food

is

to

be

marketed

as

a

‘yoghur t’

t hen

it

has

services

be

made

using

t hese

two

bacteria

t hat

can

sur vive

in

milk,

respire

for

(milk

sugar)

and

make

lactic

commonly

acidophilus

added

to

is

anot her

yoghur ts.

species

This

is

of

bacter ium

because

it

has

t hat

unique

is

are

benecial

to

human

to

sur vive

stomach

acid

healt h.

before

not

conditions

of

climate.

gut

it

has

This

infections.

promote

a

many

healt h

benets

‘good

of

bacter ial

in

t he

break

Firstly,

it

is

highly

enter ing

our

resilient

intestines

to

t he

gut

har mful

known

as

a

wall

and

down

‘pro-biotic ’

which

is

promote

for

its

why

it

the

in

human

aerobic

anaerobic

biogas

page

118).

generators

Make

a

list

of

all

the

and of

microorganisms

and

add

to

and,

microorganisms

environment,

often

an

t hat

you

work

through

the

book.

acidic

cause

ability

is

as

to

now

yoghur t.

brands

can

diarrhoea

is

bind

of

Lactobacillus

bacteria’

This

to

deter

t herefore

leading

and

wellbeing.

is

found

Today,

gassiness

It

ability

helps

positive

commonly

t hese

an

acid

many

sewage

proper ties

it

secondly,

works

although

conditions

uses

able

in

also

(see

t hat

provide

Bacteria

acid. wastes,

Lactobacillus

us.

t he treatment

lactose

also

to

help

and

because

yoghur t

to

so

are

acidophilus.

alleviate

bacteria

to

an

based

brands

symptoms

contribute

t hese

marketed

Leading

such

increased

increase

in

on

t he

claim

as

sense

number

t hat

bloating,

in

of

t he

117

835292

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Topic

2.indd

117

08/01/2015

16:05

Cell

The

respiration

large

intestine,

digestion.

intestine

people

is

t he

Some

of

t he

yeast

for

Danone

which

t heir

uses

t hey

Yoghur t

a

per

and

ar ticial

of

to

have

to

yoghur t

a

have

of

adver tisements

also

claimed

t hat

claims

t hey

are

not

effect.

t he

large

When

consequence

intestine.

drinks

as

have

developed

extravagant

healt h

company

Bidobacter ium

of

between

However,

sucrose,

and

had

improving

antibiotics.

Spanish–French

‘bad

probiotic

have

t hereby

system

lactis,

ActiRegularis®.

contain

yeasts

exchange)

repopulate

made

population

probiotic

which

t hese

as

a

drinks

sweeteners,

Some

bacterial

have

(gas

unwanted

large

known

Bidus

of

an

have

Bidobacter ium,

as

use

t he

t he

and

also

yoghur t

and

example,

trademarked

pot

t he

in

and

bacteria

can

diseases,

bacteria

For

bacteria’

and

bacterial

yoghur ts

products.

strain

Manufacturers

diseases.

of

‘bad

yoghur ts

infections

for

probiotic

have

needs

million

yogur ts

of

t he

t hese

benecial

manufacturers

strains

out

in

antibiotics

deat h

claims

or

crowding

bacteria

following

take

special

20

The

respiratory

to

suppor ted

fr uit

by

and

of

sugars

bacteria’

yoghur ts

be

10

many

feed

on.

prevent

wit hdrawn

scientic

t hese

(fr uctose)

childhood

from

evidence.

Question

How

would

benets

of

you

design

probiotic

a

long-term

study

to

investigate

t he

healt h

yoghur ts?

tap

Biogas to

production

house

Some

types

met hane

of

bacteria

(CH

)

as

t he

sur vive

waste

entirely

product

in

of

anaerobic

t heir

conditions

respiration.

and

Met hane

release

is

a

gas

4

methane

+

CO 2

water

seal

t hat

is

a

way

to

useful

source

of

energy;

it

is

one

of

t he

gases

in

natural

gas.

One

inlet

tank

dispose

bacteria

Figure

ground pump

and

of

human,

collect

B.2.4.10

is

a

t he

animal

gas

diagram

and

plant

wastes

is

to

mix

it

wit h

t hese

produced.

of

a

small

scale

biogas

generator.

Many

of

t hese

digested

are

level

used

across

t he

world,

especially

in

remote

places

where

t here

is

no

sludge

mains (used

drainage

and

unreliable

or

non-existent

supplies

of

power.

They

are

as

fertilizer)

also

used

to

supplement

national

power

supplies,

e.g.

China

where

t here

partition

are

millions

of

t hem.

The

met hane

is

used

for

cooking

and

heating

and

(retains

may

coarse

also

be

used

to

generate

electricity.

sludge)

Questions sludge

p

Figure

B.2.4.10

generator

wastes

and

cooking

used

to

uses

A

turns

and

domestic

animal

it

into

heating

generate

and

biogas

methane

and

1

a

What

does

ATP

stand

2

Describe

the

role

3

What

the

waste

for?

b

Where

is

most

ATP

produced

in

the

cell?

human

can

gas

also

be

of

ATP

in

a

human

cell.

for

electricity

are

respiration

4

What

5

Explain

as

6

are

in

the

why

products

human

waste

long

muscle

a

aerobic

respiration,

b

anaerobic

tissue?

products

distance

of

of

anaerobic

runners

cannot

respiration

run

as

fast

in

yeast

during

cells?

their

event

sprinters.

List

the

products

that

are

made

by

bacteria

and

yeasts

for

human

consumption.

118

835292

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16:05

The

respiratory

(gas

exchange)

system

Cell

respiration

Summary

The

●

respiratory

Breathing

is

refreshes

●

●

carbon

The

airways

upper

–

lower

The

many

The

in

of

the

and

so

have

–

are

a

the

Expiration

the

increases

rate

dioxide

●

●

Vital

in

●

of

much

Respiration

ATP

is

the

in

with

into

into

air

the

blood

and

larynx

cartilage,

ciliated

and

and

which

alveoli.

prevents

epithelium

protects

exchange

that

alveoli

the

includes

from

dust.

surface.

carbon

gases

two:

bronchioles

viruses

distance

to

give

to

the

in

Gaseous

dioxide

diffuse

that

across

of

the

occurs

the

cell

linings

of

to

big

space

the

in

for

steep

oxygen

and

diffusion

to

carbon

occur

concentration

relax

the

in

part

and

thorax

oxygen

the

(chest)

contract

gradients

and

carbon

that

Air

pull

there

moves

down

intercostal

is

a

down

the

muscles

ribcage.

of

muscles

the

the

the

ribcage

the

brain.

increases,

altitude

and

relax

and

diaphragm

atmosphere

by

so

to

external

decreases,

blood

drugs,

of

atmosphere.

and

diaphragm

central

the

thorax

the

muscles

raise

than

of

of

alveoli.

than

controlled

some

a

diaphragm

the

the

is

diffusion

concentrations

enlarging

lungs

the

for

maintain

the

Diaphragm

of

total

series

from

falls

air

under

air

is

during

mass

contents

the

the

in

force

the

forced

increases

e.g.

body

the

into

pressure

and

It

up

if

of

lungs

out.

the

carbon

exercise.

all

influence

the

dioxide

mitochondria

efficient

in

air

is

movement

breathed

fully

reactions

energy

that

cilia,

occurs

and

currency

cells,

out

after

breathing

inflated.

glucose

respiration

inside

of

is

are

mainly

the

from

occur

that

lungs

chemical

energy

that

requires

and

where

that

of

the

to

all

such

synthesis

of

as

of

the

the

inside

cells

to

fat.

cells.

It

is

energy-

active

proteins

transport

and

membranes.

respiration

carbon

of

triphosphate)

membranes,

Aerobic

so

macronutrients,

processes

of

volume

possible

transferring

manufacture

are

Inspired

blood

muscles

the

as

(adenosine

consuming

●

is

air

energy

involved

across

lungs.

diffuses

breathing.

release

●

by

and

The

the

dioxide

by

higher

anxiety,

throat

epithelium

oxygen

that

the

push

is

lined

blood

when

breathing

capacity

as

so

concentration

Smoking,

rate

it

open

This

area

contract

volume

so

of

is

short

and

carbon

happens

The

divided

bronchi,

gaseous

of

with

dome

ribs

held

of

out.

are

bacteria,

maintained

Intercostal

gravity.

The

a

air

inside

abdomen

thorax.

●

is

gradient.

fibrous

tract

out

continually

surfaces:

achieved

pressure

between

of

is

diffuses

blood.

surface

are

and

capillaries.

and

pressure

central

●

the

well-ventilated

Inspiration

as

body’s

between

monoxide

the

the

is

cells.

diffusion

into

oxygen

nose/mouth,

tract

such

the

there

oxygen

are

air

so

trachea,

tract

The

well-supplied

for

lower

tract:

tract:

and

large

of

lungs

continually

exchange

thin

–

air

system

respiratory

air,

the

the

dioxide

●

the

form

is

alveoli

are

–

dioxide

respiratory

alveoli

Gaseous

–

the

mucus-secreting

between

●

in

respiratory

exchange

the

movement

air

collapsing.

particles

●

exchange)

respiratory

lower

airways

the

the

and

–

(gas

it

oxygen.

water.

most

releases

of

Many

the

the

The

of

ATP

energy

products

the

is

to

of

reactions

produced.

make

aerobic

occur

Aerobic

about

30

in

respiration

the

respiration

molecules

of

is

ATP .

119

835292

CSEC

HSB

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Topic

2.indd

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16:05

Cell

The

respiration

●

Anaerobic

do

not

molecule

cells

respire

carbon

●

The

not

first

the

falling

The

a

●

●

When

in

scar

T ar

tissue

also

not

the

●

are

Carbon

of

having

away

to

Bacteria

gives

of

the

and

stage

ATP

is

of

lactic

they

two

sure

that

each

muscle

require

breaking

acid

only

Cells

for

exercise,

that

breathing

is

the

but

down

(lactate).

molecules

of

ATP

checking

lungs.

the

airways

gently

to

see

These

but

if

the

stages

are

firmly

chest

should

is

be

unaided.

is

a

off

stimulant

addictive

tar

airways.

the

–

making

most

and

It

the

yet

carbon

claim

it

has

monoxide.

damages

airways

smokers

drugs.

mucus-secreting

blocks

available.

produced

system

the

cells

and

in

cilia

to

so

that

secrete

response

they

more

to

damage

and

cells

and

are

to

leading

form

many

to

tumours

vessels

through

takes

cancer-causing

airways

blood

spread

cancer

that

the

grow

blocking

combines

can

be

bread

lactic

used

of

that

to

for

or

the

and

body

years

to

chemicals.

mutation.

which

airways.

to

form

develop

the

is

birth

the

is

women

to

an

made

milk

to

human,

sewage

to

blood.

exploited

Y oghurt

causes

in

in

pregnant

breakdown

and

haemoglobin

giving

yeasts

making.

acid

generators

so

birth

respiration

with

transported

especially

premature

are

lining

can

The

Cell

These

division

spread

cancer

secondary

sufficiently

cells

cancers

before

symptoms.

that

and

make

biogas

Lung

but

Anaerobic

making

●

a

it

the

carcinogens

cells

monoxide

smokers,

●

in

lungs

any

oxygen

of

stimulates

up

is

into

It

of

Instead

product

involves

third

gone

is

exchange)

respired.

breathes

one

burnt,

fills

controlled

elsewhere.

the

oxygen

ATP

strenuous

lots

efficient

(gas

forms.

DNA

break

there

it

is

stage

no

During

end

less

nicotine.

lining

contains

through

can

is

is

the

is

less

glucose.

glucose

has

person

It

the

which

damage

is

effect.

beating;

mucus,

air

from

breathing

mouth;

the

tobacco

of

there

much

producing

much

second

that

and

respired.

water

is

rescue

tobacco

damages

stop

●

until

drug

and

the

person’s

showing

calming

T ar

of

is

energy

molecule

stage

repeated

●

per

when

rapidly,

the

respiration

obstructed;

into

that

very

all

dioxide

made

occurs

mitochondria

glucose

getting

Anaerobic

are

their

of

can

without

to

respiration

use

respiratory

reduce

This

who

is

are

at

underweight

commercially

by

go

the

bacteria

sour

plant

and

and

volume

serious

all

risk

of

baby.

in

brewing,

that

form

animal

for

greater

respire

wine

lactose

yoghurt.

wastes

in

works.

120

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The

respiratory

(gas

exchange)

system

Practice

8

Practice

Section

1

Which

carcinogenic

substance

is

found

in

Questions

cigarettes?

Questions A

nicotine

B

tar

C

carbon

D

sulphur

A

Which

of

t he

following

statements

best

describes

vital

monoxide

dioxide

capacity? 9

A

The

maximum

volume

of

air

taken

in

During

inspiration,

air

travels

t hrough

t he

lar ynx

and

during into

which

of

t he

following?

inhalation

B

C

The

maximum

The

maximum

af ter

D

The

a

deep

capacity

volume

of

of

air

air

in

t he

t hat

can

be

move

gas

volume

of

air

taken

in

t he

A

diffusion

B

active

C

osmosis

D

trachea

D

bronchiole

during

10

exchange,

from

bronchus

C

breat h

minimum

During

oesophagus

B

exhaled

inhalation

2

A

lungs

by

alveoli

which

to

t he

process

does

Which

of

oxygen

t he

Carbon

blood?

dioxide

A

Which

of

t he

following

is

not

needed

for

respiration

B

carbon

glucose

D

enzymes

Which

of

t he

following

1

Ribs

2

Volume

3

Diaphragm

4

External

raised

A

1,2,4

B

1,3

4

16

0.04

21

4

a

16

describes

b

Identify

c

Fill

inspiration?

in

the

t he

flowing

of

t horax

Air

decreases.

intercostal

t he

muscles

following

enters

t he

relax.

The

air

t hen

and

t hen

is

not

a

characteristics

of

t he

a

air

splits

sacs

is

blood

humans.

tract.

[1]

about

air

[5]

ows

tract

into

t hrough

called

into

The

two

air

t hrough

t he

t he

nasal

lar ynx

t he

cavity.

(voice

t he

smaller

t hen

tubes

passes

called

t hrough

called

even

which

called

at

t heir

have

ends.

Carl

was

in

a

car

An

accident

emergency

and

had

stopped

responder

t he

scene,

administered

ar tificial

who

was

first

resuscitation

to

supply

revive

Carl.

lining

dioxide

due

to

being

t he

B

almost

C

lower

D

greater

diffuses

t he

from

carbon

t he

dioxide

________________

same

blood

into

t he

concentration

t hat

in

t he

alveoli.

in

t he

ii)

alveoli.

four

Identify

t hat

as

t he

List

major

resuscitation.

t he

will

ar tificial

same

as

steps

in

administering

component

help

ar tificial

[4]

t he

victim

resuscitation

impor tance.

of

t he

who

and

exhaled

is

state

air

receiving

its

[2]

t han

2

a

i)

Name

do

t he

par t

of

t he

respirator y

tract

where

t han

gas

humans

respirator y

in

passage

ventilation

A

What

exchange

following

area

i)

blood

t he

tube

branches

help

Carbon

exchange

gas

on

Thin

t he

respirator y

moves

into

breat hing.

Rich

gaseous

surface?

surface

Good

terms

gaseous

for

and

d Low

of

t hrough

contracts.

smaller

exchange

7

site

blanks

.

of

t he

[3]

upwards.

2,3,4

This

between

breat hing.

3,4

Which

79

B

Differentiate

small

6

79

79

which

D

(%)

21

79

box)

C

Nitrogen

(%)

dioxide

C

B

Oxygen

B

and

A

air?

C

Section

1

5

expired

to

place?

oxygen

D

about

transpor t

A

C

tr ue

breat hing

take

4

is

(%)

0.04

D

3

following

t he

reactions

of

anaerobic

respiration

in

ii)

produce?

A

carbon

dioxide

B

carbon

dioxide

C

lactic

D

et hanol

List

exchange

t hree

surface

iii)

and

lactic

acid

State

[1]

characteristics

found

t he

listed

occurs.

in

impor tance

above

in

a

of

humans.

ii)

of

t he

gas

exchange

[3]

each

characteristic

[3]

acid

and

carbon

dioxide

121

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Practice

b

The

Questions

The

diagram

exchange

in

below

shows

t he

site

of

gas

4

Anaerobic

respiration

microscopic

humans.

a

Define

respiratory

occurs

(gas

bot h

in

exchange)

humans

system

and

in

organisms.

anaerobic

respiration.

[2]

air

b

i)

Write

a

word

respiration Low

in

to

humans.

show

anaerobic

[2]

concentration

ii)

Explain

t he

humans.

c High

equation

i)

Write

impor tance

of

t his

reaction

in

[3]

an

equation

to

show

anaerobic

concentration

respiration

in

yeast.

[2]

X

ii)

Red

blood

5

X

and

ii)

Draw

arrows

direction

move.

iii)

State

in

Charlene

now.

t he

What

ii)

3

One

has

State

is

i)

State

in

on

move

during

process?

t he

Gas

X

gas

[1]

diagram

to

and

show

Gas

Y

name

of

in

exchange.

gas

she

Gas

smoking

was

one

sign

of

t he

and

Define

Explain

a

Y

t hat

The

Two

of

of

term

a

What

for

wit h

five

are

of

t he

Number

of

smoked

per

two

types

vital

you

below

capacity

would

[3]

effects

on

t he

healt h

and

[2]

expect

cigarettes

t he

for

10

vital

capacity

years

to

var y

of

from

[3]

shows

smoking

t he

relationships

lung

cigarettes

day

between

cancer.

Annual

death

cancer

per

rate

100

from

000

0

10

1-14

78

is

the

t his

[2]

ability

to

lung

men

15-24

127

≤25

250

respire.

characteristic

occur

in

Constr uct

bar

above.

graph

of

t he

data

in

t he

[3]

[1]

following

of

table

respiration

which

Describe

in

1

t he

trend

seen

in

t he

graph.

[2]

compares

humans.

Explain

Respiration

how

smoking

cigarettes

can

lead

to

[6]

d Respiration

Give

t he

cancer.

names

of

[3]

two

ot her

diseases

t hat

smoking

2

can mitochondria

a

humans.

lung

Factors

severe

State

bronchitis.

iii) t he

have

[3]

respiration.

[1]

respiration

t hey?

Complete

anaerobic

t he

humans.

years

ii) i)

to

organisms.

non-smoker.

table

b

by

explain

reaction

[2]

disease.

things

impor tance

types

can

smoking

cigarette

are

example,

t his

during

energy

how

table

i) ii)

t he

person

t hat

will

of

smoking

b

t he

released

of

[2]

t his

living

Gas

cigarettes

diagnosed

of

organisms.

X

named

body.

a

c

bronchitis?

characteristic

a

will

which

been

Recently,

i)

Y

what

[2]

involved

c

Gas

by

t he

is

uses

Cigarette

of

exchange

Energy

t hree

X

Gas

a

impor tance

d

i)

Using

cells

lead

to

ot her

t han

cancer.

[2]

of

Location

Cytoplasm

of

cells

cells

6

______________,

Sue

an

Reactants

is

par ticipating

hour

before

t he

in

a

race

school

she

sprint

drinks

a

event.

spor ts

About

drink

half

to

glucose

provide

______________.

a Carbon

energy

Suggest

t he

for

t he

main

respiration

nutrient

in

t hat

her

t he

muscles

spor ts

drink

dioxide, ______________,

supplies

______________,

and

explain

t he

advantage

of

taking

such

a

Products

drink

______________.

before

t he

race.

[4]

______________.

b

Number

of

Explain

during molecules

t he

Sue

race

can

and

develop

how

she

an

oxygen

will

be

debt

able

to

repay

per about

molecule

how

ATP

30

2

t his

debt.

[5]

of

c

glucose

At

home,

Amanda

ii)

For

Respiration

above,

explain

identified

produced

iii)

Describe

as

in

1

described

what

carbon

cells.

t he

role

in

happens

dioxide

t he

to

table

t he

when

it

product

Sue

is

and

her

fascinated

sister

how

the

bread

word

equation,

how

sister

with

was

Amanda

the

bread

made.

bread

is

share

and

Explain,

made

a

sandwich.

asked

using

using

her

the

yeast.

[6]

is

[3]

of

ATP

in

t he

cell.

[3]

122

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Unit

B

The

B.3

B.3.1

The

role

of

circulatory

blood

system

Learning

By

Why

have

a

circulatory

the

organisms

do

not

need

a

circulator y

system.

The

t he

surface

of

a

single-celled

organism

to

t he

centre

be

is

ver y

oxygen

can

reach

all

of

t he

mitochondria

in

t he

cell

by

diffusion

dioxide

can

pass

out

in

you

explain

why

t he

same

way.

Also

t here

is

enough

humans

need

a

system

and ●

carbon

topic

to:

small

circulatory

so

this

able

distance ●

between

of

system? should

Single-celled

end

outcomes

state

the

composition

of

surface

blood

membrane

in

contact

wit h

t he

surroundings

to

obtain

enough

oxygen

and ●

to

lose

all

t he

carbon

dioxide

produced

in

list

the

substances

respiration.

transported

Many-celled

distances

animals

between

efcient

enough

increase

t he

rate

have

surface

to

of

much

and

deliver

more

centre

oxygen

diffusion

to

bulk

are

all

t hrough

t han

much

t he

an

single-cell

greater

cells

of

organism

and

t he

organisms.

diffusion

body.

decreases

As

is

The

●

describe

many-celled

surface

exposed

demonstrate

area

size

and

and

t he

in

ot her

Maths

The

an

area

surface

most

such

by

animals

as

Figure

by

blood

cells

blood

cells

ratio

It

they

is

do

and

several

three

but

as

wit h

sizes

t he

shows

exchanging

ammonia

relatively

ratio

t hat

oxygen

steeply.

and

little

wit h

an

red

●

describe

the

process

of

clotting.

body

exercise

between

and

of

white

distances

ver y

mat hematical

Calculating

different

for

bodies

simple

and

will

surface

increase

carbon

in

dioxide

urea.

ratio

volume

shows

of

t his.

A

blood

1

cylinders

system,

of

such

volume.

imagining

B.3.1.2

circulatory

wastes

because

compact

surface

volume

to

its

spheres,

principle

less

skills

and

area

organism

have

surroundings.

animals

relatively

excreting

Surface

t heir

impor tance

volume

comes

animals

to

the

roles

not

blood

Most

in

the

of

animal

is

calculated

quite

not

difcult

have

cubes.

A

regular

three

we

the

the

surface

surface

dimensional

can

area

area

of

of

shapes,

demonstrate

the

‘animals’.

‘animals’,

does

dividing

measure

However,

cube-shaped

these

by

to

A,

B

and

C.

Animal

C

has

a

not.

p

Figure

B.3.1.1

medical

from

Phlebotomists

specialists

people

for

who

take

laboratory

are

blood

analysis

A B C

1

mm

3

mm

5

p

Figure

1

Calculate

Figure

2

B.3.1.2

the

Three

cube-shaped

surface

area

and

area

to

‘animals’

the

of

mm

increasing

volumes

of

each

size

of

the

‘animals’

in

B.3.1.2.

Calculate

the

surface

volume

ratio

for

each

‘animal’.

123

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The

role

of

The

blood

3

Explain

Copy

your

q

why

T able

‘animal’

B.3.1.1

C

(or

has

a

type

circulatory

into

a

system,

spreadsheet)

but

and

circulatory

‘animal’

add

the

A

system

does

results

not.

of

calculations.

T able

B.3.1.1

3

Cube

of

Surface

Volume / mm

Surface

area:

2

side / mm

area / mm

volume

ratio

1

2

24

8

3.0:1

96

64

1.5:1

216

216

1.0:1

3

4

5

6

4

Use

ratio

the

5

Describe

6

Explain

7

Using

the

Humans

will

we

✔

tip

not

do

skin

circulatory

system

is

as

system.

the

It

is

comprising

organ

system

the

heart,

blood

red

of

t he

The

not

and

platelets

confuse

(gaseous

it

white

and

with

t hese

and

much

so

wit h

circulator y

most

surface

to

to

volume

t he

why

from

distances

obtain

carr y

of

humans.

the

surface

area:

1:1.

diffusion

animals,

system

area

axis).

area

explain

that

as

surface

graph.

graph,

to

of

horizontal

the

simple

surface

graph

your

less

adequately

body

As

on

a

the

measure

table

is

cells

cells

enough

a

to

your

of

curve

on

we

t he

are

enough

have

a

body

too

substances

large.

oxygen

special

to

surface

area

and

Also

even

if

for

from

our

gas

all

t he

blood

–

the

circulator y

a

tissue

t hat

system

is

consists

composed

of

of:

cells

suspended

in

a

liquid

which

is

blood

plasma.

the

exchange)

comprising

in

humans

draw

body.

human

mostly cells,

and

the

difficult

trillions

have

of

to

volume

cardiovascular

an

●

vessels,

of

table

(put

also

cells

known

is

permeable.

exchange

The

it

figures

supply

was

your

shape

ratio

have

not

in

volume

the

why

volume

Exam

results

against

Do

respiratory

●

system

trachea,

water

lungs

blood

vessels

smallest

and

between

of

–

tubes

t hese

blood

t hat

tubes

and

carr y

are

t he

‘leaky’

respiring

blood

to

to

allow

all

par ts

exchange

of

of

t he

body.

The

substances

tissues

diaphragm.

●

t he

hear t

–

a

muscular

Functions

of

The

of

functions

amino

of

heat

acids,

blood

oxygen,

t hroughout

defence

against

reproduction,

page

the

t he

t he

t hat

pumps

blood

around

t he

body.

blood

include

carbon

disease

e.g.

organ

body

t he

for

t hrough

penis

transpor t

dioxide

is

and

temperature

t he

made

action

erect

of

substances,

antibodies,

of

by

t he

regulation

white

t he

use

(see

blood

of

e.g.

glucose,

distr ibution

page

cells

blood

197),

and

(see

244).

124

835292

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16:07

The

circulatory

Blood

The

system

The

role

of

blood

structure

composition

of

human

blood

is

represented

as

a

char t

in

Figure

B.3.1.3.

blood

plasma

water

55%

blood

90%

dissolved

erythrocytes

substances

10%,

e.g.

amino

(red

blood

cells

45%

leucocytes

cells)

(white

blood

thrombocytes

cells)

(platelets)

glucose,

acids,

hormones,

antibodies,

proteins

salts,

(fibrinogen,

prothrombin)

p

Figure

Role

B.3.1.3

of

Plasma

is

Composition

t he

liquid

par t

in

Table

information

in

ot her

T able

blood

t he

blood.

which

Its

also

functions

shows

you

in

transpor t

where

to

are

nd

more

Units.

B.3.1.2

transported

in

dioxide

hydrogen

of

B.3.1.2

Substances

Carbon

the

plasma

summarised

q

of

plasma

–

as

Site

of

into

the

absorption

respiring

carbonate

Site

of

delivery

Unit

plasma

and

page

number

tissues

lungs

Unit

B2

pages

98–101

ions

Nutrients

small

intestine

liver

and

all

other

Unit

B1

pages

80–81

organs

Water

small

and

large

kidney

intestine

Hormones

ductless

(endocrine)

specic

glands

Urea

and

all

other

Unit

B5

pages

179–183

organs

for

liver

target

each

organs

Units

hormone

B6

and

219–224

kidneys

Unit

B5

B7

and

pages

252–254

pages

175

and

179–183

Heat

muscles

and

liver

skin,

over

Alt hough

made

are

blood

from

described

Red

Red

numerous

numbers

are

worn

as

a

cells

uid,

have

notice

t hat

impor tant,

all

Unit

almost

but

B5

pages

187

and

197–202

half

specic,

of

it

(45%)

functions

is

which

cells

cells,

of

These

and

body

below.

blood

blood

behaves

cells.

lungs

the

or

our

ever y

out.

er yt hrocytes

blood

day

In

a

to

cells.

They

replace

healt hy

as

t he

t hey

are

also

made

cells

human

are

t hat

each

in

are

drop

known,

bone

are

marrow

destroyed

of

t he

blood

most

in

huge

because

contains

t hey

about

3

5

million

so

red

numerous

widest

blood

blood

t hat

if

cells.

t hey

This

is

equivalent

clumped

toget her

to

1

mm

t hey

of

blood.

would

block

They

all

but

are

t he

p

vessels.

Figure

B.3.1.4

micrograph

Red

blood

cells

do

not

contain

nuclei

or

any

organelles

such

t hat

t here

are

Instead

over

250

t he

cytoplasm

million

is

full

of

haemoglobin

haemoglobin.

molecules

in

In

this

blood

electron

you

can

see

red

as blood

mitochondria.

of

It

each

is

estimated

red

blood

cells

biconcave

cells

with

disc

(yellow)

their

characteristic

shape,

and

white

platelets

blood

(pink)

125

835292

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HSB

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Topic

3.indd

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08/01/2015

16:07

The

role

of

The

blood

cell.

our

8

Haemoglobin

blood,

Figure

from

B.3.1.6

our

enzyme

lungs

t hat

carbonate

ratio

can

for

pack

surface

shape.

gaseous

in

Large

more

No

to

allow

area

to

nucleus

haemoglobin.

membrane

through

surface

exchange.

Elastic

them

is

t he

pigment

which

makes

t hese

cells,

and

red.

to

shows,

to

t he

catalyses

ions

for

t he

cells

t he

role

of

of

our

haemoglobin

body.

conversion

transpor t

in

t he

Red

of

is

blood

carbon

plasma.

to

transpor t

cells

also

dioxide

This

into

enzyme

oxygen

contain

an

hydrogen

helps

t he

blood

to

volume

remove

so

plenty

of

carbon

dioxide

as

it

ows

t hrough

respiring

tissues.

cell

Our

squeeze

ability

to

transpor t

oxygen

is

affected

by:

capillaries.

●

Anaemia

page

●

–

t he

most

common

Carbon

can

2

Produced

in

the

µm

●

marrow

of

some

bones.

Live

be

monoxide

High

carried

and

17

spleen.

weeks

then

Usually

are

destroyed

between

4

to

6

is

a

lack

of

iron

in

t he

diet

(see

–

this

by

altitudes

–

red

gas

This

blood

t here

is

binds

permanently

binding

cells

less

reduces

and

oxygen

causes

in

t he

the

to

haemoglobin

volume

drowsiness

air

at

high

of

forming

oxygen

and

even

altitudes,

that

death.

but

for

people approximately

cause

64).

carboxyhaemoglobin.

liver

molecule

system

µm

As

Biconcave

appear

circulatory

in

living

or

travelling

t here

acclimatise

by

forming

many

more

red

the

blood

million

cells.

3

per

mm

and

blood.

some

Function

carbon

is

to

transport

oxygen

dioxide.

q

p

Figure

B.3.1.5

lungs

(high

Red

oxygen

blood

T able

B.3.1.3

Comparisons

concentration)

Feature

White

Nucleus

Yes

Mitochondria

Yes

Size / µm

8

Contains

haemoglobin

red

haemoglobin

oxygen

(HbO

to

).

blood

(Hb)

form

(Note

white

blood

cells

and

red

to

blood

cells

blood

Red

cells

blood

cells

No

No

20

8

No

Functions

haemoglobin

between

cells

Yes

Defence

against

•

phagocytosis

•

production

Transports

infections:

carbon

oxygen

and

dioxide

in

cell

combines

of

antibodies

with

oxyhaemoglobin

that

one

molecule

White

blood

cells

8

of

Hb

can

carry

four

oxygen

molecules)

White

oxyhaemoglobin

haemoglobin

‘picks

up’

and

and

some

takes

it

splits

oxygen

of

the

back

up

to

blood

the

dioxide

lungs

There

are

and

vacuoles.

t hat

(low

oxgen

several

in

B.3.1.6

transporting

The

also

1

mm

made

of

in

bone

blood

but

mar row.

t he

There

number

are

about

var ies

quite

10

a

00 0

lot.

different

types

of

white

blood

cell,

including

phagocytes

cells,

are

from

two

bone

pat hogens

types

of

marrow

and

cell

debris,

phagocytes.

to

organs,

and

digest

Monocytes

such

as

t he

are

lungs

t hem

wit hin

phagocytes

and

intestines,

concentration)

t hey

spread Figure

are

in

engulf

There

move

where

p

cells

lymphocytes.

Phagocytes

tissues

cells

3

white haemoglobin

carbon

to

blood

give

role

oxygen

of

of

remain

providing

pat hogens.

an

impor tant

Neutrophils

travel

in

line

t he

of

defence

blood

as

a

against

‘rapid

t he

reaction

haemoglobin

force’;

blood

during

searching

Lymphocytes

concentrated

system

and

invading

Lymph

Figure

an

are

in

spread

lymph

are

on

protein

pathogens.

pathogens

is

pat hogens

pour

and

widely

nodes

reproductive

nodes

process

for

t hey

out

of

t he

destroying

t hroughout

in

system

organ

which

t hem

t he

systems

are

bone

t he

marrow

by

body,

like

most

t he

phagocytosis.

but

t he

into

t hey

gut,

likely

tend

to

be

respirator y

to

be

infected

by

microorganisms.

B.3.3.8

special

infection

part

page

of

the

1 42.

molecules

Antibodies

together

known

as

in

lymphatic

Many

that

kill

of

them

protect

microbes

clumps

system

produce

against

directly

making

which

them

you

antibodies

bacteria,

or

help

easier

can

see

which

vir uses

and

phagocytes

to

engulf.

in

by

This

are

other

‘sticking’

clumping

agglutination.

126

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The

circulatory

system

The

Monocyte

Neutrophil

role

of

blood

Lymphocyte

nucleus

partially

permeable

membrane

8–10 20

µm

12

µm

µm

vesicles

containing

enzymes

p

Figure

B.3.1.7

The

different

types

of

white

blood

cell

bacteria

phagocyte

foreign

p

‘recognises’

Figure

Looking

this

at

phlebotomist

technician

microscope

through

a

1

Look

2

Use

the

collected

a

the

some

haematology

A

Figures

‘flowing’

it

digests

them

using

enzymes

and

B,

B.3.1.9

blood

from

laboratory

and

and

added

a

B.3.1.10

a

person

smeared

blue

are

stain

two

who

the

to

was

blood

in

good

across

make

the

photographs

health.

two

white

that

blood

he

took

microscope

carefully

at

Figures

drawings

in

B.3.1.9

Figure

and

B.3.1.7

p

Figure

B.3.1.9

Blood

p

Figure

B.3.1.10

smear

A

(x300)

B.3.1.10.

to

identify

the

cells

that

you

can

see

in

photographs.

3

Make

4

Use

drawings

the

you

of

each

magnifications

cell

type

given

to

from

the

calculate

photographs.

the

diameters

of

the

cells

that

draw.

Label

their

your

drawings

with

the

names

of

the

cells

and

add

notes

about

appearance.

Suggest

relative

of

in

light

by

cells

slides,

visible.

them

them

yourself

blood

A

cells

ingests

Phagocytosis

A

6

it

around

B.3.1.8

Tr y

5

the

bacteria

how

you

numbers

would

of

red

use

photographs

blood

cells

and

like

white

these

blood

to

calculate

cells

in

a

the

sample

blood.

Platelets

Key

Blood

smear

B

(x400)

term

! Platelets

are

tiny

non-nucleated

cell

fragments

formed

in

t he

bone Platelets

marrow.

In

a

healt hy

human,

t here

are

approximately

250

000

in

Small

fragments

of

cells

ever y that

do

not

have

nuclei;

these

cell

3

mm

of

blood.

They

are

involved

in

blood

clotting,

a

vital

process

which fragments

prevents

entr y

of

excessive

blood

pat hogens

loss

t hrough

from

damaged

damaged

blood

vessels

and

prevents

t he

start

the

release

blood

substances

clotting

to

process.

skin.

127

835292

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08/01/2015

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The

role

of

The

blood

Figure

Key

is

terms

B.3.1.12

formed

shows

when

a

t he

mesh

major

of

stages

protein

in

bres

t he

clotting

traps

red

circulatory

process.

blood

cells

The

to

system

clot

make

itself

an

! impenetrable

Prothrombin

dissolved

changes

in

An

the

into

inactive

plasma

thrombin

enzyme

blood

vessels

barrier

release

when

wounding

chemicals

t hat

occurs.

star t

t his

The

platelets

and

damaged

process.

which

during

Calcium

ions

platelets

to

have

several

roles

in

blood

clotting

including

stimulating

blood

release

substances

t hat

activate

an

enzyme

in

t he

plasma.

This

clotting.

Thrombin

The

plasma

converts

that

enzyme

in

enzyme

conver ts

anot her

enzyme

thrombin.

plasma

protein,

prothrombin,

into

t he

active

blood

brinogen

The

nal

step

in

t he

cascade

is

conversion

by

t hrombin

to

of

t he

plasma

protein

brinogen

into

brin

t hat

forms

a

mesh

to

trap

brin.

blood Fibrinogen

protein

that

A

globular

changes

blood

from

A

brous

brinogen

clotting

to

prevents

T able

protein

during

form

a

blood

Red

blood

mesh

of

Exam

entr y

of

pat hogens.

Summary

table

of

the

functions

of

blood

cells

cell

Functions

cell

1

Transports

oxygen

2

Transports

some

from

lungs

carbon

to

dioxide

tissues

from

blood

(cell

is

cell

fragment)

prepared

such

out

Protection

system

use

if

you

between

and

to

lungs

if

as

phagocytosis

2

producing

Protection

from

blood

brinogen.

someone

is

by:

1

It

by

antibodies

releasing

plasma

is

decient

used

in

factors

by

in

to

activate

removing

diagnostic

the

t he

blood

blood

tests,

such

clotting

process

clotting

as

t he

test

to

iron.

is

a

have

cells,

good

acts

to

on

tissues,

blood

organs

tissues

tip

circulatory

distinguish

B.3.1.4

blood

White

loss.

nd

to

and

that

protein

example

loss

formed

Ser um

The

blood

brin

Platelet

✔

stop

clots.

T ype

Fibrin

and

plasma

into

q

when

cells

organ

systems.

Think

platelets

release

protein

the

prothrombin

of

a

list

blood

heart

starting

cells

and

and

with

red

ending

blood

and

with

white

enzyme

thrombokinase

the

vessels.

thrombin

acts

on

blood

calcium

protein

ions fibrinogen

and

vitamin

also

K

needed

fibrin

fibrin

strands

cells.

These

a

p

Figure

B.3.1.12

scab

The

at

trap

dry

the

red

out

wound

stages

in

blood

and

form

site

blood

clotting

128

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The

circulatory

Case

system

Declan’s

Declan

is

about

t hat

will

of

he

but

is

right

not

small

not

be

do

blood

A,

and

B

B

D.

This

serious

operation.

of

blood

medical

Declan’s

doesn’t

and

t hat

may

require

t he

cell

ABO

D

is

and

during

t he

a

is

blood

are

of

will

Before

of

blood

group

always

A+,

take

impregnated

blood

type

cer tain

supply

nurse

t hat

major

wrong

he

a

are

operation.

order

t hinks

cards

two

doctors

t he

to

because

using

t he

him

His

have

mot her

it

identify

give

staff

matter

test

if

D

cell

Test

groups.

blood

and

If

t hey

t hat

a

wit h

did

could

B,

present

blood

of

t he

and

O.

blood

t hen

In

t he

ABO

are

Rhesus

blood

g roup

in

(so

blood

is

Rhesus

system;

types

(or

not

A

because

t here

positive

do

people.

g roup

called

system

known

which

most

blood

four

Rhesus

membrane

molecules

system

There

t he

is

surface

minor

transfusion

of

group

t he

cell

Rhesus

monkeys).

AB

t he

in

t heir

more

molecules

Rhesus

A,

on

ot her

in

are

just

D

it

two.

positive)

negative

(or

negative).

cards

drop

drop

surface

t hen

not

also

molecule

in

system:

is

molecules

are

consideration

surface

present

simply

have

There

discovered

t he

A

cells

and

are

t he

was

If

type.

blood

t hey

a

begin,

antibodies

t his,

usually

is

of

of

like

t he

water

blood

is

is

one

in

added

added

Figure

to

to

B.3.1.13

each

each

test

test

are

area

area

used

to

and

to

test

activate

mixed

Declan’s

t he

wit h

blood.

antibodies.

t he

liquid.

A

The

Anti-A

rst

t hree

t hat

in

t he

t he

areas

test

detect

card

four t h

is

A,

B

and

working

D.

The

properly.

four t h

The

area

blood

is

a

control

should

not

to

AB+.

If

they

shows

t he

results

for

Declan’s

positive

test

with

negative

all

three

with

all

test

of

areas,

them

-

Nome

blood.

the

the

person’s

blood

When

work

out

carr ying

that

out

there

are

operations

eight

t hat

different

type

blood

is

O−.

group

staff

almost

always

uses

may

blood

blood

require

of

t he

types

blood

same

You

-

Focha

de

can

ABO

stocks

are

low

it

may

be

possible

to

use

a

example

blood

of

type

O−

can

be

given

to

all

as

blood

ot her

Rhosus

t he

so

does

it

has

not

none

of

stimulate

t he

t he

t hree

cell

patient

surface

to

-

Fecha

Signature

-

2003-09-04

Firma

SA

Figure

B.3.1.13

Declan’s

A,

antibodies

The

results

blood

to

after

the

card

group,

blood

molecules,

produce

Data

patient.

find

out

B

or

t hat

his

blood

group.

Was

his

groups mother

because

Anti-

altogether.

to

for

Dirección

transfusions,

type

different

Nacimianto

Pos.

adding

If

-

is

p

hospital

Adrress

BMJ

A

probably

control

coagulate

Born

tests

Anti-D/Anti-Rho

area.

B.3.1.13

blood

Anti-B

check

Name

Figure

If

blood

fatal.

Red

as

of

group

transfusions

cer tain.

of

blood

have

can

blood

sample

special

to

need

operation

t he

role

study

Find ing

t he

The

D

correct?

and

will

control

anti-A

anti-B

anti-D

Person

agglutinate

in

t he

emergencies

Immediately

t he

patient’s

blood

if

and

t here

before

blood

an

is

block

no

blood

time

to

operation,

wit h

t he

a

blood

vessels.

nd

out

nurse

Blood

t he

by

type

patient’s

repeats

supplied

of

t he

t he

test

blood

O−

blood

to

is

used

type.

cross

W

match

bank.

X

Figure

B.3.1.14

(W,

Y

X,

and

shows

Z).

results

Identify

t he

of

testing

blood

blood

groups

of

from

t he

four

four

people

people

tested.

Y

Sometimes

t he

t he

t hemselves.

patient

blood

t hat

is

This

used

in

transfusions

happens

in

cases

of

has

rare

been

donated

blood

groups

by

wit h

Z

uncommon

if

t he

types

patient

diseases.

In

is

of

molecules

worried

most

cases,

about

on

t he

t hough,

t he

surface

risks

blood

of

of

t he

infection

comes

from

blood

wit h

a

cells

and

blood-borne

blood

bank

and

is

p

Figure

tests

B.3.1.14

of

four

Results

of

blood

people

129

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The

role

of

The

blood

normally

as

HIV

People

and

to

q

t heir

Blood

is

kept

future

blood

groups

T able

donated

volunteer

result

rarest

blood

as

blood

to

le

so

been

t he

r un

blood

t he

donations.

groups

in

donate

on

tested

will

staff

Blood

low.

Jamaican

for

major

vir uses,

such

of

rst

t he

banks

Table

have

t heir

blood

blood

bank

know

of ten

B.3.1.5

nd

shows

t hat

t he

tested

how

supplies

of

distribution

of

population.

B.3.1.5

group

Percentage

the

of

Blood

group

Percentage

population

the

23.0

A−

2.0

B+

20.0

B−

1.0

AB+

23.0

AB−

0.5

47.0

O−

3.5

Jamaican

National

Blood

Transfusion

Service:

of

population

A+

O+

Source:

has

system

hepatitis.

who

t his

label

t he

safe

and

circulatory

http://www.nbts.gov.jm/pages.

php?id=6

1

Choose

Table

and

draw

B.3.1.5

to

an

effective

teach

a

group

way

of

to

present

younger

t he

information

students

about

in

blood

groups.

2

Explain

being

3

why

it

is

admitted

Explain

why

impor tant

to

hospital

blood

is

cross

to

know

for

t he

blood

group

of

patients

operations.

matched

immediately

before

an

operation.

In

September

repor ted

getting

4

5

its

t he

stocks

Jamaican

of

O+

National

and

AB−

Blood

blood

Transfusion

were

low

and

A+

Ser vice

was

low.

Suggest

AB−

t hat

2014,

why

t he

Jamaican

blood

bank

had

low

stocks

of

O+,

A+

and

blood.

How

would

you

encourage

people

to

give

blood?

Questions

1

Why

2

State

3

Explain

4

Describe

the

role

5

Describe

the

process

6

Explain

7

State

8

How

high

9

do

single-celled

three

functions

why

the

three

does

organisms

oxygen

role

of

ways

the

of

of

is

body

need

a

circulatory

system?

blood.

not

included

in

T able

B.3.1.2.

lymphocytes.

of

phagocytosis

platelets

in

not

which

a

in

the

red

acclimatise

using

bullet

points.

blood.

blood

to

the

cell

low

is

adapted

content

of

to

its

function.

oxygen

in

the

air

at

altitude?

Using

the

between

circulatory

cells,

system

tissues,

as

organs

an

and

example,

organ

explain

the

relationship

systems.

130

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The

circulatory

B.3.2

system

Heart

Heart

structure

and

function

Learning

By

Structure

of

the

the

end

hear t

is

a

muscular

organ

t hat

pumps

blood

t hrough

blood

t he

body.

Figure

B.3.2.1

shows

what

t he

human

hear t

be

from

t he

muscle

which

looks

of

describe

front.

The

tissue

t hat

makes

up

most

of

t he

hear t

is

is

shown

found

here

and

nowhere

else

in

t he

body.

Cardiac

in

are

relate

Figure

B.3.2.2.

connected.

Notice

Cardiac

t hat

muscle

t he

bres

bres

are

at

t he

bottom

branched

communicate

wit h

each

ot her

and

contract

like

of

right

right

coronary

the

explain

left

atrium

left

coronary

blood

explain

the

(b)

A

vein

cava

drawing

of

the

heart

aorta

and

the

major

blood

vessels Figure

is

two

pumps

lying

side

by

side

(Figure

B.3.2.3).

Each

side

blood

from

into

ventricle

t he

from

t hat

ventricles.

There

to

is

veins

atrium

so

and

to

t he

of

walls

atrium

resistance

atria

ows

do

into

an

contraction

ventricle

Each

no

move,

which

whose

ventricle

atrium

t he

to

not

t he

are

of

walls

t he

each

a

at

side

as

from

into

prevent

t hick

low

blood

as

Blood

blood

t he

an

t he

atrium

ar ter y.

(a)

viewed

The

dark

An

external

from

red

the

view

front

structure

at

of

of

the

right

of

the

heart

is

the

left

the

atrium

ows

Valves

backow

of

hear tbeat.

not

blood

ow

have

on

during

atria

pumps

atrium.

forces

B.3.2.1

heart

receives top

Notice

pulse.

ventricle

body.

blood

pressure

ventricle

the

between

heart

explain

artery

p

a

‘lubb–dupp’

the

artery

B.3.2.1

hear t

the

of

atrium

descending

The

within

functions

cava

vena

Figure

their

arch

cardiac

p

structures

to

toget her.

left

right

and

heart

so

●

vena

structure

the

t he

t his

●

aortic

the

of

heart

sound

t hey

you

muscle

●

photograph

topic

to:

cardiac

the

tissue

this

like

●

is

outcomes

able

function

viewed

function

vessels ●

around

and

heart should

The

structure

and

t hick

as

t he

pressure

as

t he

t he

walls

into

blood

of

t he

t he

ventricles.

does

not

have

far

ventricles.

Did

you

know?

? The

walls

muscle

pumps

of

t he

of

to

t he

pump

blood

body.

t herefore

ventricles

to

t he

t he

The

t he

blood

lungs

lungs

blood

are

are

t hicker

against

and

t he

sof t,

pressure

in

a

because

greater

lef t

have

resistance.

ventricle

spongy

t he

t hey

organs

The

pumps

because

pulmonar y

ar ter y

much

right

blood

t hey

does

more

to

are

not

cardiac

ventricle

t he

full

rest

of

have

air;

to

be

Cardiac

type

of

fatigue.

of

high

as

lungs

do

not

give

much

resistance

to

t he

ow

of

is

a

much

circulation

and

lef t

give

a

higher

ventricle

t han

t he

greater

because

has

right

t he

resistance

organs

resistance

to

create

a

to

are

t he

high

to

t he

not

ow

like

blood.

pressure

of

t he

To

blood

lungs;

overcome

and

in

t he

t hey

rest

are

t his

t herefore

of

t he

much

denser

resistance,

has

–

–

is

the

that

other

two

smooth

become

only

does

not

types

and

fatigued

if

blood.

they

There

The

muscle

skeletal

ver y

muscle

muscle

a

t hicker

t he

wall

work

muscle

body

is

is

like

for

in

long.

tubular

the

attached

Unit

too

gut;

to

the

Smooth

organs

skeletal

in

the

muscle

skeleton

(see

B.4).

ventricle.

131

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Heart

structure

and

The

function

circulatory

system

T o get an idea of pressure and resistance, think about turning on a tap attached

to a hose pipe. If you turn on the tap a little way, no water comes out of the

other end of the hose pipe because the pressure is too low. Now gradually turn

the tap further to give a higher pressure and you nd that water will overcome

the resistance of the hose pipe and emerge from the far end.

carotid

superior

vena

artery

cava

pulmonary

vein

pulmonary aorta artery

left right

p

Figure

B.3.2.2

Cardiac

muscle

tissue

atrium atrium

from

a

taken

has

ventricle.

with

had

fibres

an

This

photograph

electron

colour

(brown,

added

pink

was

microscope

to

and

show

and

semilunar

inferior

vena

muscle

purple),

a

bicuspid tricuspid

capillary

fibres

the

(orange)

that

and

transmit

ventricles

modified

impulses

(green)

(mitral)

though

cords

(x750).

p

(valve

Figure

=

deoxygenated

=

oxygenated

B.3.2.3

showing

the

blood

blood

Structure

pathway

ventricle

of

taken

the

by

heart

and

associated

blood

vessels

blood

bicuspid

B.3.2.4

Human

heart

tendons)

ventricle

left

Figure

valve

valve

muscle

right

p

valve

cava

valve

dissected

semilunar

to

show

the

the

heart

Y ou

can

at

left

the

see

side

top

the

with

of

very

the

the

top

thick

wall

of

the

tricuspid

left

its

ventricle,

tendons.

B.3.2.3

and

the

bicuspid

Compare

valves

of

photograph.

valve

with

valve

and

Figures

B.3.2.5 X Y

p

Figure

of

the

Figure

B.3.2.5

viewed

X

Y

is

is

B.3.2.5

from

t he

t he

A

drawing

made

of

a

cross

section

of

the

heart

at

the

level

valves

shows

above.

valve

valve

at

at

t he

t he

a

section

The

base

base

across

valves

of

of

t he

t he

t he

labelled

aor ta

hear t

X

and

where

pulmonar y

it

to

Y

show

t he

four

valves

are

t he

semi-lunar

joins

t he

lef t

ar ter y

where

it

valves.

ventricle.

joins

t he

right

132

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The

circulatory

ventricle.

t he

When

ar teries,

you

t he

can

system

see

t he

blood

in

t he

Heart

pressure

ows

in

back

drawing

t he

ventricles

towards

so

closing

t he

t he

is

less

t han

ventricles,

valve

lls

t he

t he

preventing

pressure

t hat

Study

✔

tip

hear t.

It

The

heart’s

is

and

blue

conventional

The

hear t

people

t here

beats

have

is

a

at

about

hear t

special

rates

tissue

pacemaker.

Muscle

impulses

regular

in

72

beats

higher

and

known

t he

per

t he

minute,

lower

t han

sino-atrial

sino-atrial

alt hough

node

t his.

node

In

perfectly

t he

which

contracts

and

right

is

t he

emits

healt hy

atrium

does

hear t’s

inter vals.

These

impulses

spread

across

t he

not

colour

own

electrical

t he

t he

rest

of

t he

cardiac

muscle

to

contract,

rst

t he

blue.

can

increase

along

speed

also

that

blue

to

lungs.

in

and

blue.

blood

red

as

Blood

This

changes

it

is

Deoxygenated

goes

red,

atria

red

and

oxygenated

blood

blood

is

is

and

red.

These

colours

are

not

ventricles. very

brain

the

red

hear t

bright

t hen

show

in

blood

mean

from

through

dark

stimulating

blood

deoxygenated

never

at

to

pacemaker oxygenated

to

function

into

Red

We

and

in

‘pockets’

backow

structure

up

speeds

and

ner ves

t he

up

decrease

t hat

hear t

t he

end

rate

t he

on

and

hear t

t he

to

rate

by

sino-atrial

slow

it

sending

node.

down.

The

impulses

We

send

from

out

hormones

t he

to

use

that

impulses

different

is

blue

the

contain

adrenaline

people

hear t.

muscle

closed

bicuspid

diagrams

colour

of

with

because

veins

deoxygenated

decided

that

blood

light-coloured

in

skin.

semilunar

closed

tricuspid

in

someone

sphincter

semilunar

valves

so

valves

bicuspid

and

tricuspid

valves

open

and

valves closed

open

deoxygenated

oxygenated

a

Diastole

(between

blood

blood

beats) b

p

Figure

Blood

The

B.3.2.6

ow

The

through

contraction

state,

when

contractions

t he

of

a

the

chamber

cardiac

of

heart

during

systole

one

(atria

heart

contract)

c

Ventricular

on

each

side

of

t he

hear t

is

t he

hear t

not

is

called

contracting,

systole.

is

called

The

diastole.

Study

✔

resting

contract

and

relax

at

t he

same

time.

The

The

same

and

relax

time

as

involves

Stage

from

(a):

t he

venae

backow

Stage

each

of

(b):

t hem

stage,

so

and

t he

t hat

atria

systole

two next

a

different

complete

time

hear t

from

beat

is

t he

atria

called

a

but

at

cardiac

section

t he

cycle

the

on

blood

understand

an

heart

is

if

have

animation

you

or

a

much

ow

easier

access

YouTube

to

to

clip.

stages.

and

ventricles

pulmonar y

t he

tricuspid

is

–

relax

veins.

pulmonar y

bot h

volume

Blood

muscles

blood

One

and

from

t heir

increases.

bicuspid

–

at

tip

and

blood

Semilunar

ar ter y

and

enters

valves

aor ta

into

t he

hear t

prevent

t he

any

ventricles

(a)).

Atrial

consequence,

ot her.

cavae

blood

B.3.2.6

contract

following

Diastole

t he

(Figure

and

contract)

two through

ventricles

(ventricles

beat

The

atria

systole

heart

of

muscle

the

Atrial

at

will

valves

one

higher

into

t he

contract

decrease

slightly

around

forced

atria

t he

so

into

t he

t hat

ventricles

t he

veins

same

t he

pressure

pulmonar y

way

at

blood

ows

As

B.3.2.6

venae

a

pressure

t hrough

(Figure

and

time.

wit hin

t he

(b)).

cavae

At

t his

constrict

ventricles.

133

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Heart

structure

and

The

function

Stage

(c):

Ventricular

contracted.

decreases

t he

The

so

t hat

ventricles

valves

are

higher

blood

is

t he

t han

t hat

into

in

Use

happens

what

you

t han

As

t he

t he

–

bot h

relax.

pressure

shut.

Written

What

now

greater

pushed

ows

systole

atria

in

t he

t hem

t hat

t he

ventricles

As

in

increases.

t he

pressure

ar teries,

t he

pulmonar y

contract

ventricles

atria,

in

t he

and

af ter

contract,

t he

so

t he

valves

aor ta

t he

bicuspid

also

are

(Figure

system

atria

t heir

Eventually

ventricles

semilunar

ar ter y

circulatory

have

volume

pressure

and

in

tricuspid

becomes

pushed

open

and

B.3.2.6(c)).

Activity

during

have

one

just

heart

read

and

beat

the

diagrams

of

the

heart

to

answer

these

questions.

1

What

happens

during

to

a

ventricular

2

What

are

3

What

is

4

Suggest

the

the

a

roles

role

role

photographs

of

of

for

and

the

volume

systole

the

the

the

Explain

why

the

left

6

Explain

why

the

walls

the

bicuspid

semilunar

valve

diagrams

5

and

when

the

pressure

in

the

ventricles

contract?

tricuspid

valves?

valves?

the

is

the

and

tendons

of

ventricle

of

b

ventricles

that

thicker

atria

you

can

see

in

the

heart.

are

than

much

the

right

thinner

ventricle.

than

those

of

the

ventricles.

7

Using

take

8 0

0.5

1.0

1.5

Figure

in

What

B.3.2.3,

getting

type

of

from

blood

describe

the

right

vessel

is

the

pathway

atrium

a

the

to

the

aorta;

that

a

red

blood

cell

would

aorta.

b

the

vena

cava?

2.0

time / s

Figure

B.3.2.7

is

a

timeline

of

changes

that

occur

as

the

heart

beats

three

times.

diastole

Use

p

Figure

Figure

B.3.2.7

to

answer

these

questions.

B.3.2.7

9

Calculate

10

List

11

At

the

12

At

q

T able

a

what

and

b

heart

sequence

what

valves

the

stages

open,

in

rate

of

stages

in

B.3.2.1

the

cardiac

The

parts

of

the

Function

cavae

these

atrium

ventricle

Pulmonary

arteries

Pulmonary

veins

ventricle

Aorta

one

heart

cycle

do

the

tricuspid

and

cycle

do

the

semilunar

beat.

bicuspid

valves

a

open,

heart,

blood

its

associated

ows

from

the

blood

body

to

vessels

the

right

and

their

atrium

functions

through

deoxygenated

blood

from

the

body

and

pumps

it

into

the

ventricle

Pumps

deoxygenated

Deoxygenated

Oxygenated

Receives

left

Left

during

veins

Receives

right

atrium

occurs

close?

Deoxygenated

Left

minute.

close?

Venae

Right

per

that

cardiac

b

Structure

Right

beats

events

the

and

in

blood

blood

blood

ows

ows

oxygenated

into

from

from

blood

the

the

the

pulmonary

heart

lungs

from

the

to

to

the

the

artery

lungs

left

pulmonary

through

atrium

veins

these

through

and

arteries

these

pumps

it

veins

into

the

ventricle

Pumps

oxygenated

Oxygenated

through

this

blood

artery

blood

ows

(the

into

from

largest

the

the

in

aorta

left

the

ventricle

to

the

rest

of

the

body

body)

134

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The

circulatory

Heart

lungs

Figure

●

If

are

‘lubb’

●

–

search

for

sounds

The

as

t he

of

to

t he

body

closure

of

bicuspid

t he

can

borrow

makes

and

a

t hat

such

as

t he

blood

in

ar teries

from

hear t

be

action

pumped

is

t he

pulmonar y

of

in

normal

be

t he

sounds

hear t.

valves

(sof ter

stet hoscope

from

(see

These

hear t

and

by

par ticular

(louder

sound)

hear

t hem

sounds

t he

for

online.

number

of

yourself

If

you

different

problems.

t he

aor ta

are

t he

of

and

tissue.

builds

up

t he

blood

t he

high

ar ter y

ventricles

and

pressure

system.

The

t hat

enables

contraction

of

t he

pressure.

pulmonar y

As

stretched

a

circulator y

expand.

remain

contract,

As

t he

relatively

t he

aor ta

ventricles

constant

and

relax,

t hese p

t he

recoil

As

The

its

t he

as

person’s

ar ter y.

ow.

The

As

a

cuff

cuff

is

to

are

a

t he

is

This

to

is

t he

blood

of

blood

gradually

t he

bit

t he

not

an

kilopascals

t he

SI

for

unit

unit

(kPa).

so

and

a

fall

to

t he

t he

stop

rst

t he

systolic

band

for

t he

hears

80

in

Figure

B.3.2.8

stethoscope

of

along

stretches

his

to

A

doctor

listen

to

uses

the

a

heart

beat

patient

in

ar ter y

of

blood

sound

and

diastole.

pressure.

of

t his

ar ter y

up

and

owing.

systole

at

largely

an

goes

resistance

mmHg

in

ow

t he

pressure.

depends

example

t he

(millimetres

so

blood

ow

diastolic

pressure,

owing

between

brachial

blood

and

in

vessel

blood

t he

reducing

of

The

blood

ventricular

mmHg

for

in

impor tant

blood

friction

blood

keep

nurse

t he

narrower,

to

pressure

pressure

mmHg

use

or

during

t he

causes

pressure

deated

pressure

to

ver y

band.

system,

a

is

ventricle.

resistance

inated

doctor

more,

systolic

120

is

keep

lef t

becomes

t he

recoil

elastic

t hrough

increases

cuff

an

t he

vessels

ows

vessel

t he

of

and

circulator y

disease,

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wit h

blood

pressure

take

profession

pressure.

mmHg

a

t his

t he

This

pressure

diastole

blood

happens

pressure

medical

of

result

deates

pressures

blood

If

may

corresponding

t he

model

t hrough

walls

diameter.

blood

during

B.3.2.9).

t his

t he

can

blood

staff

Figure

original

which

diameter.

Medical

(see

You

recoils

wit h

narrowing

t he

t heir

travels

and

ease

to

maintain

and

blood

blood

on

to

ar teries.

systole

function

sound).

hear t

sur prised

indicate

hear t

source

elastic

ar ter y

t he

around

main

contain

helping

and

valves.

tricuspid

valves

of

may

of

sounds

t he

semilunar

you

sounds,

movement

‘lubb–dupp’

t he

sounds’

hear t

pressures

vessels

structure

pressure

to

t hey

listen

demonstrations

‘hear t

ventricles

The

of

you

some

pumping

blood

if

t he

by

closure

t he

Blood

and

see

to

to

breat hing,

closure

possible,

listen

used

caused

–

‘dupp’

or

are

during

B.3.2.8)

sounds

Heart

sounds

Stet hoscopes

t he

system

for

in

to

of

blood

t hen,

The

as

two

normal

diastolic.

we

arm

t he

blood

These

mercur y)

book

t he

in

for

will

The

blood

conver t

p

Figure

B.3.2.9

Measuring

blood

pressure

135

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Heart

structure

and

The

function

q

T able

the

Part

B.3.2.2

Shows

circulatory

of

the

blood

pressures

circulatory

Maximum

pressure

atrium

Left

ventricle

artery

(in

Figure

cuff

B.3.2.10

records

The

blood

blood

pressure

pressure,

heart

Femoral

to

it

blood

the

is

the

flow

patient’s

displayed.

data

systolic

to

diastolic

kPa)

per

and

phone

person’s

pressure

(12.7

transmits

smartphone

The

the

kPa),

beats

and

is

the

is

pressure

the

leg)

blood

(kPa)

0

10.7

16.0

10.7

16.0

10.7

4.7

2.0

1.3

0.7

0.4

0

vein

cava

data

send

mmHg

heart

Minimum

Right

atrium

1.1

0

Right

ventricle

3.3

0

where

can

doctor.

147

pressure

the

of

rate Vena

and

parts

16.0

Capillary

p

blood

(kPa)

1.1

Aorta

Femoral

different

system

system.

system

Left

in

circulatory

95

rate

His Pulmonary

artery

3.3

1.1

Pulmonary

vein

1.1

0.8

(19.6

mmHg

is

77

minute

Many

doctor s

blood

pressure.

pressure

and

and

clinics

Figure

use

a ppa ra tus

Th e re

t he

to

t he

da t a

allow

are

n ow

t h ey

shown

ma ny

co lle ct

do c tor s

to

in

Fig u re

dig it al

c an

be

mon itor

B.3. 2. 9

meter s

stored

t h eir

for

and

to

me asur ing

sen t

patie n ts

measure

to

b lood

su rger ies

remotely

(se e

B.3.2.10).

Pulse

The

ar ter ies

relax

over

feel

is

t he

wr ist

is

we

centre

decrease

t he

hear t

t he

and

adrenal

where

Several

it

factors

yourself

affect

ar ter y

72

alter

rate

t he

glands

in

increases

affect

opposite),

hear t

rate.

of

to

for

t he

t hick

t he

pass

movement

pulse

wr ist

when

near

t hat

to

muscle)

rate.

An

be

and

bones).

area

stimulate

t he

Hormones,

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stress.

hear t

pulse

and

over

required.

times

over

recoil

t hey

to

t he

you

felt

on

The

skin

can

are

t he

in

t he

inside

usual

pulse

rate

t he

pulse

This

places

and

ar ter ies

minute.

impulses

as

t he

t he

diet

per

contract

where

bone.

passes

pulse

alter

ner ve

hear t

or

felt

passes

beats

the

be

common

ar ter y

ner ves

sends

t he

ventr icles

to

muscle

most

carotid

earlier,

pacemaker

by

like

The

(where

which

saw

cardiac

or

t he

r m

t he

swelling

approximately

Factors

As

when

slight

pulse.

(where

t he

rate

a

somet hing

neck

of

expand

causing

hormone

It

travels

in

t he

brain

pacemaker

too,

stimulate

adrenaline

in

t he

is

called

to

t he

increase

t he

produced

bloodstream

to

t he

rate.

rate,

stress,

for

example

which

of ten

exercise

leads

to

(see

t he

Tr y

t his

secretion

of

adrenaline.

136

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The

circulatory

Tr y

The

system

this

effect

of

Heart

structure

and

function

yourself

exercise

on

pulse

rate

Requirements

●

Timer

●

Graph

A

good

and

a

Start

to

how

heart

this

determine

long

person

is,

wrist

your

own

as

rate

monitor

five

someone’s

takes

by

shown

pulse,

After

it

the

activity

your

1

electronic

paper

way

see

tter

or

to

return

quicker

their

nding

your

in

then

Figure

sit

minutes

heart

beat

pulse

quietly

your

is

normal

to

pulse

a

returns

set

to

ve

for

you

their

resting

amount

its

counting

When

for

measure

after

and

B.3.2.11.

down

count

tness

to

it.

are

of

resting

Place

heart

exercise.

rate

The

value.

two

condent

ngers

about

over

taking

minutes.

30

seconds

and

multiply

p

the

Figure

pulse.

answer

by

2

to

give

your

pulse

rate

in

beats

per

at

2

Wait

30

seconds

and

repeat

step

1.

Repeat

again

and

calculate

the

Y ou

A

to

should

good

to

to

down

4

After

5

30

an

or

the

seconds

your

Wait

30

your

pulse

flight

10

pulse

for

that

of

activity

is

to

if

you

see

are

how

in

long

good

it

your

heart

Repeat

8

Plot

9

a

Find

of

step

6

graph

raise

five

your

times,

heart

rate,

running

such

on

the

as

out

from

30

the

task,

seconds

then,

exercise

for

your

heart

your

wrist

thumb

for

two

Repeat

this

again,

and

heart

rate

graph

your

heart

investigation

good

subjects.

level

of

Y ou

might

activity

neck.

Do

here

not

when

taking

the

use

pulse

measure

and

your

multiplying

measure

multiplying

your

by

heart

by

heart

rate

by

2.

rate

by

1 40

counting

1 00

80

60

40

20

2.

0

rate

against

has

returned

to

its

resting

return

how

to

long

normal

it

takes

(see

from

Figure

1

2

with

Make

other

sure

people.

first

that

it

Friends

is

safe

and

for

and

like

to

their

see

if

there

recovery

is

a

correlation

4

the

to

5

6

7

8

9

10

Time/ min

before

during

after

task

task

task

end

B.3.2.12).

family

them

3

value.

time.

approximately

rate

to

p

Figure

B.3.2.12

heart

A

rate

graph

showing

might

be

what

before

a

and

members

do

between

a

period

of

exercise.

Notice

how

the the

exercise.

the

120

after

make

on

160

person’s

10

or

walking

spot

down.

of

seconds

until

of

own

either

rate

0

7

felt

health.

takes

ups.

sit

end

for

and

30

will

stairs

press

the

seconds

this

fitness

exercise

after

your

be

exercise.

activity

doing

doing

counting

after

a

with

your

nim rep staeb /etar t raeH

on

up

can

rest.

continue

Decide

and

at

assess

normal

minutes

6

rate

only

way

return

3

pulse

T aking

pulse

your your

mean

B.3.2.11

The

minute.

their

heart

case

rate.

rate

about

recover

takes

five

after

and

the

some

a

half

exercise

time,

in

this

minutes,

has

to

stopped

Questions

1

What

2

Where

3

What

4

Which

5

What

6

Explain

the

7

In

terms

is

is

the

of

the

used

heart’s

blood

part

is

are

for

a

pacemaker?

pressure?

the

contraction

heart

What

How

does

produces

b

relaxation

does

it

‘120/80’

the

highest

of

heart

control

(cardiac)

the

heart

muscle?

rate?

mean?

pressure?

pulse?

why

the

blood

pressure

does

not

decrease

along

the

length

of

arteries.

which

part

of

the

blood

system

does

the

greatest

fall

in

pressure

occur?

137

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The

circulatory

Learning

By

the

end

The

system

B.3.3

outcomes

of

this

topic

The

be

able

define

the

term

circulatory

all

the

structure

of

the

circulatory

hear t

the

to

their

have

of

a

t he

double

body,

a

circulation

red

blood

(Figure

cell

will

B.3.3.1).

pass

This

t hrough

To

understand

t his,

look

at

Figure

B.3.3.1.

Imagine

a

red

in

to

t he

lungs.

return

to

its

Look

at

how

original

many

times

it

goes

t hrough

t he

hear t

position.

veins

and

B.3.3.1

shows

t he

two

circuits

taken

by

t he

blood:

t he

pulmonar y

of

systemic

circulations.

Pulmonar y

circulation

is

t he

circulation

of

blood

capillaries

from

t he

hear t

to

t he

lungs

and

back.

Systemic

circulation

is

t he

circulation

functions

of

●

circuit

system

structure

and arteries,

humans

each

twice.

cell

order

Figure relate

for

human

in

●

mammals,

t hat

and

blood

function

system

system

t he

describe

circulatory

double

means

●

system

to:

Like ●

system

you

Double should

circulatory

circulatory

describe

the

structure

blood

t he function

of

the

from

t he

hear t

to

t he

rest

of

t he

body

(not

t he

lungs)

and

back

to

and

hear t.

lymphatic

system

The advantages of a double

●

describe

how

tissue

fluid

circulation are

LUNGS

and

lymph

are

oxygenated

formed. Low

blood (red on diagrams) and

O

PULMONARY

2

High

CO

deoxygenated blood

CIRCUIT

2

(blue)

are kept separate and the left

Key

terms

ventricle pumps blood at a much

!

higher pressure into the systemic

Double

circulation

Blood

travels

circulation than the right ventricle through

the

heart

twice

in

one High

pumps blood to the lungs.

O 2

complete

circulation

of

the

body. Low

CO 2

Oxygenated

almost

fully

blood

Blood

saturated

with

that

Figure B.3.3.2 shows a more

is

detailed version of the circulatory

oxygen; SYSTEMIC

it

carries

its

maximum

volume

system. You will recognise some of

of CIRCUIT

oxygen

and

less

carbon

dioxide

than

the names of the blood vessels from BODY

deoxygenated

blood.

Deoxygenated

has

about

oxygen

carbon

it

70%

can

of

the

carry

dioxide

earlier Units and you will learn

blood

that

p

Figure

B.3.3.1

u

Figure

B.3.3.2

human

double

Double

about others in Units to come.

circulation

maximum

and

than

Blood

is

The

details

of

the

HEAD

more

circulatory

ARMS

in

pulmonary

oxygenated

&

system

artery

pulmonary

vein

blood. superior

vena

LUNGS

cava

aorta

Heart

hepatic

vein

hepatic

artery

LIVER

hepatic

portal

inferior

vena

vein

STOMACH

cava

&

INTESTINES

renal

vein

renal

artery

KIDNEYS

t

Figure

body.

B.3.3.3

This

The

virtual

computer LOWER

generated

image

shows

circulatory

system

upper

of

part

the

in

the

&

BODY

LEGS

the

body Deoxygenated

blood

Oxygenated

blood

138

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The

circulatory

system

The

circulatory

system

Artery

This artery

small

ver y

muscular

wall

wit h

lumen

many

t he

elastic

ar ter y

to

bres

allows

wit hstand

endothelium

and

maintain

a

high

blood

collagen

pressure.

fibres

elastic

and

fibres

smooth

muscle

×10

Vein

Veins

have

much

t hinner

vein

walls

elastic

fibres

t han

pressure

is

t he

much

muscle

lower.

large

as

and

blood smooth

ar teries

lumen

easily

blood

collagen

fibres

They

if

t he

can

increases

during

exercise.

semilunar

expand

volume

as

of

happens

Veins

valves

to

have

prevent

endothelium

backow.

×120

Capillary

The lining of capillaries is capillary

made from one layer of very

thin

endothelium

thin cells. There are tiny holes (one

cell

thick)

between the cells which make

capillaries ‘leaky’. This is ideal

for the exchange of substances

(e.g. glucose) between the

blood and tissue uid. As the

cells are thin there is a very

short distance for diffusion of

oxygen and carbon dioxide.

×4000

p

Figure

B.3.3.4

The

structure

of

arteries,

veins

and

capillaries

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The

circulatory

The

system

●

In

Unit

t he

B.1

delivering

●

In

Unit

circuit

In

B.2

Unit

and

q

saw

you

B.5

to

and

t he

t he

one

followed

t he

t he

t hat

system

blood

from

t hrough

●

you

digestive

hear t

in

will

taking

t he

t he

pulmonar y

you

hepatic

liver.

por tal

Note

it

t hat

vein

t he

circulatory

transpor ts

liver

has

blood

two

system

from

blood

vessels

away.

pat hway

of

pulmonar y

blood

t hrough

ar ter y

to

t he

t he

pulmonar y

lungs

and

back

vein.

follow

t he

circulation

from

t he

hear t

to

t he

kidneys

back.

T able

B.3.3.1

Summary

table

showing

the

differences

between

arteries,

veins

and

capillaries

Artery

Thick,

Vein

elastic

wall

Capillary

Thinner

wall

with

less

elastic

Very

tissue

No

valves

Valves

Blood

under

Blood

ows

Normally

high

in

pressure

spurts

carries

oxygenated

How

Veins

so

●

blood

low

●

A

capillary

ows

low

pressure

smoothly

is

not

carries

Skeletal

muscle

t he

from

legs.

Valves

t he

–

vein

Par tial

As

t he

–

t hese

deoxygenated

veins

back

vacuum

t he

in

one

cell

valves

Blood

under

ows

Oxygen

heart

low

and

carbon

exchanged

Connects

pressure

smoothly

an

dioxide

here

artery

to

a

vein

to

push

the

the

blood

helping

if

we

are

contract

hear t.

The

all

blood

the

to

standing

by

get

or

skeletal

t hey

pressure

way

back

back

to

sitting

muscle,

squeeze

in

the

to

the

veins

the

hear t.

upright.

par ticularly

t he

veins,

pushing

t he

muscle

contain.

t he

B.3.3.5).

to

the

surrounded

muscles

t hey

i.e.

heart

in

region

are

to

back

to

essential

prevent

(Figure

the

pressure

head

t hese

blood

to

blood

sufcient

are

wall,

Blood

are

Carries

low

following

direction

B.3.3.6

it

heart

at

–

t he

Figure

under

Blood

returns

blood

that

The

against

p

the

Gravity

in

●

from

blood

carr y

hear t.

●

Blood

blood

Carries

is

No

Normally

blood

thin

thick

backow

As

a

result,

of

blood

t he

when

blood

must

ow

in

squeezes

one

hear t.

chest

–

during

inspiration

t he

pressure

in

t he

chest

network

cavity

decreases

atmospheric

move

along

a)

air

t he

muscle

(see

to

page

be

103).

drawn

major

veins

This

into

and

relaxed

par tial

our

into

b)

vacuum

lungs,

t he

muscle

but

it

not

also

only

causes

causes

blood

to

hear t.

contracted

blood

pushed

vein

through

open

valve

valves

closed

valve

prevents

back

flow

p

Figure

B.3.3.5

The

action

of

semilunar

valves

in

veins

140

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16:07

The

circulatory

Tissue

If

blood

cells

system

never

t he

lef t

t he

can

t hrough

of

back

one

walls

to

layer

t he

blood

nutrients

t hrough

Refer

of

of

ver y

need.

ar teries

t he

Figure

vessels,

t hey

t hin

B.3.3.4

t hin

and

walls

to

cells

it

would

Oxygen

veins

of

see

substances

capillaries

because

be

able

to

nutrients

t hey

are

supply

cannot

too

body

leave

t hick,

but

t hey

t he

pores

lining

of

between

t he

capillar y

t hem.

This

consists

to

and

be

exchanged

bat he

t he

body

by

diffusion.

cells

form

t he

The

small

makes

tissue

molecules

it

easy

t hat

term

!

leave

uid

Tissue

uid

surrounds

Figure

B.3.3.6

shows

a

dense

capillar y

network

under

t he

epit helium

in

Figure

close

to

Note

t hat,

●

a

t here

B.3.3.7

is

in

a

t hrough

●

red

t he

are

which

t he

●

at

surrounded

gaining

far

end

of

t he

blood

and

t he

blood

pressure

pressure

t he

of

t he

t he

of

each

cell

in

a

tissue

is

It

is

that

of

blood

formed

by

plasma.

ver y

by

leaves

the

ar teriole

ions

end

from

t he

of

t he

blood

wit h

and

near

a

so

and

to

ions)

fatty

taken

in

t he

much

nutrients

acids,

and

(e.g.

t hey

t he

capillar y

exchange

passing

out

t he

loss

t he

vessel

pressure

of

inside

t heir

products

wastes

t he

venule

acids,

by

and

venule,

blood

t he

stay

which

ot her

t he

result,

t hat

leads

proteins,

glucose,

cells

t hen

molecules

wall

now

tissue

and

vitamins

is

of

less

uid

into

waste

(e.g.

is

from

causes

t han

t he

reabsorbed

veins.

products

carbon

metabolites,

given

dioxide,

excess

out

by

cells

unwanted

ions)

the

capillaries

at

end

capillary

the

t he

and

nutrients

between

As

uid

and

fluid

uid

dioxide

fall.

t hat

e.g.

and

capillar y

tissue

at

molecules

tissue

oxygen

to

uid:

pressure

molecules,

amino

of

how

uid

capillar y

friction

capillaries

tissue

small

t he

oxygen

tissue

showing

blood

carbon

t he

into

of

large

hormones),

t he

high

forces

lining

cells,

substances,

(e.g.

diagram

formation

relatively

blood

cells

a

The

cells.

capillar y.

capillaries

●

is

the

t he ltration

colon;

system

capillaries.

t hat

wit h

not

and

Key

for

circulatory

uid

wit h

pass

The

venule

arteriole

network

some

back

tissue

into

fluid

the

passes

capillaries

arteriole

the

rest

enters

of

the

the

tissue

lymph

fluid

capillaries

Key

term

!

Lymph

system.

into

p

Figure

B.3.3.7

Formation

of

tissue

fluid

and

The

It

uid

drains

lymph

in

the

from

lymphatic

tissue

uid

vessels.

lymph

141

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The

circulatory

The

system

Lymphatic

right

into

lymphatic

the

right

duct

empties

subclavian

left

vein

subclavian

Not

all

of

the

lymph

These

veins

uid

by

in

ows

in

in

small

vessels

by

muscles

nodes

t he

t he

The

lymphatic

When

a

of

to

larger

ensure

The

it

body

these

is

uid

the

inside

moved

that

slowly

squeeze

of ten;

more

energy

a

colourless

many

uid,

white

rich

the

blood

in

cells.

contain

valves;

vessels

are

(see

page

like

t he

t he

lymph

is

have

in

in

t he

system

t hrough

Figure

blood

lengt h,

These

groin,

lymph

veins

are

neck

accumulate

immune

Eventually,

of

t heir

nodes.

t he

Lymphocytes

339).

(see

Along

lymph

common

surrounding

movement

legs).

impor tant

blood

t he

of

here

response

returns

in

t he

to

neck

B.3.3.8).

exercise

person

more

star ts

the

to

exercise,

muscles

which

is

do

their

much

provided

by

muscles

more

work.

respiration.

star t

This

The

contracting

means

that

respirator y

harder

they

rate

and

need

increases

tip because

need an

organ

we

muscles

more

so

far.

It

is

(see

other

pages

organs,

105

and

such

1 12).

as

the

The

diaphragm

breathing

and

rate

hear t,

and

depth

of

both

increase

and

the

cardiac

output

of

the

hear t

also

increases

to

situated

supply the

ATP

and

have

breathing mentioned

of

the

and

into

of

B.3.3.7 .

thin-walled

valves

contraction

of

armpits.

region

system

Effects

is

(rat her

veins

and

t he

side

like

Some

Figure

intestine

and

the

of

in

drain

are

direction.

contains

par ticularly

to

system.

shown

lymph

Lymph

and

lymph

not

into

blind-ended

villi

in

is

one

is

into

vessels

lacteals

moved

spleen

are

which

movements

Lymph of

The

lymph

semi-lunar

vessels

lipids

from

Study

reabsorbed

duct

lymphatic

✔

is

drains

capillaries

vessels

vessels.

B.3.3.8

uid

Some

the

lymph

with

these

Figure

tissue

capillaries

lymph

p

system

capillaries.

capillaries

lymph

system

vein

the

thoracic

circulatory

stomach

the

body

with

the

increased

oxygen

needed

for

aerobic

respiration.

and, 3

like

It

is

the

liver,

also

cells

led

and

people

is

with

–

to

you

with

white

lymphatic

have

removed

lled

their

live

Some

spleens

without

cardiac

each

blood

tissue.

have

can

The

blood.

output

minute.

hear t

beats

volume

of

This

per

is

is

the

achieved

minute

blood

volume

by

of

out

of

in

increasing

increases),

pumped

blood

and

the

dm

the

increasing

hear t

with

pumped

hear t

the

each

rate

out

(the

stroke

beat

of

the

hear t

number

volume

of

(the

increases).

it.

cardiac

output

(volume

hear t

rate

stroke

volume

3

of

blood

from

The

in

hear t

extra

blood

dm

per

is

=

minute)

volume

t hat

(volume

of

3

pumped

of

stored

t he

per

×

minute)

blood

in

(beats

coming

liver

and

into

blood

of

t he

spleen

in

hear t

dm

per

circulation

when

at

pumped

out

beat)

during

exercise

is

rest.

142

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The

circulatory

system

The

Practical

The

beep

This

is

a

circulatory

system

Activity

test

popular

oxygen

to

names:

beep

way

support

test,

to

test

aerobic

bleep

the

efciency

respiration

test,

shuttle

of

during

runs,

the

heart

and

exercise.

multi-stage

It

lungs

has

a

tness

in

providing

variety

of

test.

Requirements

●

T ape

●

two

●

CD

measure

markers

player,

20

test

with

Y ou

apart.

1

Find

a

2

Warm

only

flat

up

with

20

beep

metres

test

apart

app,

continuously

runs,

beeps

laptop

surface

5

to

10

are

with

and

between

sometimes

that

continue

for

set

a

running

These

pre-recorded

should

rule

running

a

program

with

beeps

involves

metres

metre

person

phone

pre-recorded

This

or

per

played

this

mark

at

activity

two

minutes

called

by

if

points

doing

set

two

points

shuttle

intervals

you

that

are

are

some

in

that

runs,

of

are

exactly

kept

in

time

time.

good

exactly

jogging

are

health.

20

and

metres

apart.

stretching

exercises.

3

Start

one

the

foot

beep

on

test

or

software.

just

over

the

At

each

line.

The

beep,

beeps

you

are

need

set

to

so

have

you

at

will

least

start

to

−1

move

until

4

at

8.5

you

After

a

km

hear

while,

.

h

the

If

you

are

too

fast

you

will

have

to

wait

at

the

line

beep.

there

will

be

a

double

beep

which

indicates

the

speed

is

−1

5

increasing

by

rest

test.

of

When

read

the

you

your

before

miss

your

km

the

fitness

failing

oxygen

0.5

to

h

beep

score

keep

body

.

on

from

up

can

This

is

will

two

the

your

absorb

now

happen

consecutive

program

score.

during

or

This

at

regular

occasions,

app.

The

score

exercise.

It

is

is

intervals

stop

highest

the

the

test

level

maximum

known

as

the

for

the

and

you

reach

volume

VO

of

max

2

3

and

6

is

Warm

Try

the

measured

down

test

by

and

Bleep

in

cm

doing

compare

3

oxygen

some

your

per

kilogram

stretching

level

of

per

minute

(cm

−1

kg

−1

min

).

exercises.

tness

with

others.

Test

54.5 3

Fitness:

Next

cm

beep:

2

sec

Speed:

-1

kg

-1

min

13.5

km/h

20

p

Figure

B.3.3.9

measure

their

These

aerobic

two

students

are

doing

shuttle

m

runs

to

fitness

143

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The

circulatory

The

system

Written

The

output

of

of

a

student

measurements

q

T able

heart

were

while

system

Activity

the

Measurements

circulatory

at

made

resting

are

in

rest

of

the

and

T able

and

during

heart

during

rate

some

exercise

and

the

cardiac

strenuous

output

exercise.

The

B.3.3.2.

B.3.3.2

At

rest

During

strenuous

exercise

−1

Heart

rate

/

beats

min

3

Cardiac

During

output

and

cardiac

output

strenuous

T able

5

25

min

there

organ

160

−1

dm

exercise

organs

q

/

72

are

changes

systems.

that

ows

T able

through

in

the

distribution

B.3.3.3

the

shows

organs

of

the

the

of

blood

to

body

at

rest

of

Percentage

at

of

cardiac

Percentage

rest

Brain

output

Skin

of

the

digestive

system

Kidneys

of

during

15

6

3

26

2

4

20

80

5

5

Bones

4

1

Others

4

2

muscles

Cardiac

muscle

1

data

Calculate

in

in

the

heart

T ables

the

B.3.3.2

student’s

and

stroke

B.3.3.3

volume

cardiac

exercise

3

20

Skeletal

the

during

B.3.3.3

output

Use

the

and

exercise.

Organ

Organs

different

percentage

to

(i)

answer

at

rest,

the

and

following

(ii)

during

questions

strenuous

exercise.

2

Summarise

when

the

someone

significant

does

changes

strenuous

in

the

distribution

Calculate

the

a

4

the

organs

rate

listed

of

a

blood

at

rest,

flow

and

blood

that

occur

exercise.

3

3

of

in

b

dm

−1

min

during

that

flows

exercise.

through

Present

your

each

of

answers

in

table.

Draw

at

a

rest

Figure

bar

and

graph

to

during

B.3.3.10

compare

exercise.

as

this

a

the

rate

Consider

good

way

to

of

blood

drawing

show

flow

the

data

through

bars

like

the

organs

horizontally

as

in

this.

Skin

0

0.1

0.2

0.3

0.4

0.5

0.6

3

Rate

p

5

Suggest

T able

examples

Figure

of

the

of

blood

flow/dm

0.7

0.8

–1

min

B.3.3.10

organs

included

in

the

category

‘others’

in

B.3.3.2.

144

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The

circulatory

system

Heart

disease

Questions

1

Describe

goes

2

from

Make

3

a

pathway

lungs

table

to

that

shows

that

supply

Explain

why

the

the

left

vena

side

4

Explain

5

a

in

why

Describe

the

must

be

the

blood

in

and

organs

each

exactly

in

the

back

the

organ

to

the

body

and

flowing

the

circulation

into

same

the

as

it

it

the

names

of

the

away.

right

the

when

lungs.

and

take

system

side

volume

of

the

heart

entering

the

vein.

have

structure

blood

muscle

to

of

pulmonary

arteries

by

the

blood

volume

cava

the

taken

cardiac

vessels

in

6

the

thicker

of

walls

capillaries.

than

b

veins.

Explain

the

role

of

capillaries

in

body.

State

four

ways

in

which

blood

returns

to

the

heart

from

the

systemic

circulation.

7

Explain

8

Name

B.3.4

how

an

artery

Heart

Cardiovascular

Caribbean

the

lymph

heart

as

that

all

formed.

contains

deoxygenated

blood.

disease

diseases

in

and

is

are

other

the

parts

circulator y

Learning

most

of

the

system.

important

world.

Included

cause

These

in

this

are

of

death

all

the

categor y

in

diseases

of

By

the

of

disease

the

heart

disease

(CHD),

heart

failure,

heart

valve

disease

be

of

and

define

the

explain

disease

●

explain

effects

Coronar y

hear t

disease

angina

–

pain

you

hypertension

in

the

of

atherosclerosis

arteries

causes

heart

and

attacks

includes:

●

●

term

how

develops

heart

topic

to:

strokes. ●

Coronary

this

able

are ●

coronary

end

should

outcomes

across

t he

chest,

lef t

arm

and

shoulder

caused

describe

the

role

of

artificial

by pacemakers.

insufcient

●

coronar y

some

blood

getting

t hrombosis

cardiac

muscle

–

is

a

to

t he

hear t

blockage

star ved

of

muscle

occurs

blood

in

and

a

coronar y

dies

–t his

ar ter y

is

a

so

hear t

t hat

attack.

Key

terms

! Figure

3.4.1

muscle

The

in

shows

t he

blockage

cardiac

lef t

t he

ventricle

stops

muscle.

coronar y

t he

This

and

blood

tissue

ar teries

a

place

owing

dies

and

supplying

(C)

into

t his

where

an

a

in

of

blockage

capillaries

results

area

a

cardiac

has

supplying

hear t

occurred.

a

region

of

Coronary

condition

one

attack.

or

more

Atheroma

arch

material

of

heart

caused

on

disease

by

a

coronary

A

deposit

the

lining

A

blockage

in

arteries.

of

of

a

an

fatty

artery.

aorta

right

coronary

artery left

coronary

artery

A

t

Figure

B.3.4.1

The

heart

showing

coronary

B

arteries.

C

is

A

blocked

blood

branch

at

C

leading

cardiac

so

to

of

the

left

coronary

interrupting

the

death

of

flow

artery

of

surrounding

muscle

145

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Heart

The

disease

circulatory

system

Atherosclerosis

Key

term

!

One

of

t he

most

atherosclerosis Atherosclerosis

The

process

fatty

material

is

deposited

lining

of

of

blockages

material,

in

coronar y

par ticularly

ar teries

cholesterol,

t he

inner

wall

of

t he

coronar y

ar teries

(Figure

B.3.4.2).

These

artery

with

fatty

endothelium

streak

develops

wall

of

on

the

plaque

the

and

artery

develops

narrows

space

for

plaque

the

blood

p

Figure

Tiny

B.3.4.2

par ticles

ar teries

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146

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The

circulatory

disease

t he

are

risk

which

lack

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regular

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B.3.2.9).

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13.3

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mmHg).

excessive alcohol, take little exercise, or eat a high fat and/or high salt diet.

chances

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hypertension.

study

High blood pressure is more likely in people who smoke, are overweight, drink

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tip

above

vessel

coronar y

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numbers

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is

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Heart transplant – in ver y serious cases a heart transplant may be carried

out, but the number of these is limited by the availability of donor hearts.

Articial

Some

pacemakers

people

pacemakers.

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t he

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Figure

B.3.4.4

inserted

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An

artificial

person’s

pacemaker

chest

147

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Heart

The

disease

Maths

T able

the

q

B.3.4.1

shows

Americas

T able

skills

in

circulatory

system

2

deaths

from

cardiovascular

disease

in

ten

countries

in

2010.

B.3.4.1

Country

Population

Deaths

T otal

from

cardiovascular

of

diseases

all

number

deaths

from

1995 causes

Barbados

283 000

504

1800

Belize

324 000

325

1300

Cayman

Costa

Islands

50 000

43

270

4 805 000

6 300

21 000

11 271 000

34 710

89 000

72 000

183

572

795 000

2 079

6 300

109 000

311

700

1 337 000

4 160

13 000

318 000 000

823 360

2 656 000

Rica

Cuba

Dominica

Guyana

St.

Vincent

and

the

Grenadines

2010

Trinidad

and

Non-communicable T obago

(2008)

diseases

USA

Communicable

diseases

These Injuries

and

much Ill-defined

p

Figure

B

changes

3.4.5

in

2010

of

Pie

charts

percentages

in

death

the

in

cannot

be

compared

easily

as

the

populations

differ

so

size.

causes

to

of

show

four

the

1

Calculate

between

1995

for

each

country

listed

in

T able

B.3.4.1,

main

a

causes

gures

accidents

the

crude

the

population

death

the

deaths

rate,

which

is

the

number

of

deaths

per

100 000

of

and

of

each

country;

Caribbean

b

2

Display

the

countries

The

number

countries

3

How

this

4

5

results

are

of

as

from

easy

cases

they

would

of

your

to

see

of

you

use

calculations

at

a

coronary

become

disease

more

as

so

a

percentage

comparisons

of

total

between

deaths.

the

ten

glance.

heart

disease

is

said

to

increase

in

developed.

statistics

of

deaths

in

different

countries

to

test

statement?

Suggest

how

you

would

organisations

to

and

heart

List

cardiovascular

coronary

the

factors,

developing

Case

find

out

use

data

whether

from

there

national

is

a

and

international

correlation

between

smoking

disease.

other

coronary

than

heart

smoking,

that

increase

the

chances

of

disease.

study

Hypertension

The

✔

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tip

Non-communicable

all

by

the

diseases

organisms

viruses.

There

that

such

is

Unit

D.1

and

diseases

are

as

not

t he

Americas,

t he

ten

Organization

cause

mor tality

almost

from

maintains

two

t hirds

diseases

t hat

of

linked

all

to

non-communicable

deat hs

worldwide.

hyper tension

is

In

leading

causes

of

deat h

in

men

and

one

of

women.

caused

more

diseases

D.2.

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currently

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bacteria

much

non-communicable

World

diseases

and

about

in

Hypertension is a persistent raised blood pressure. The WHO denition of

hypertension is a systolic blood pressure that is always equal to or above

1 40 mmHg (≥ 1 40 mmHg / 18.7 kPa) and/or a diastolic blood pressure that

is always equal to or above 90 mmHg (≥ 90 mmHg / 12.0 kPa).

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The

circulatory

system

Hyper tension

is

a

Heart

risk

factor

of

disease

t hat

affects

bot h

men

and

✔ women.

High

children

and

blood

pressures

teenagers

in

have

t he

even

been

found

in

sur veys

many

different

tip

Caribbean.

as

of

Exam

of

You

Samples

disease

populations

across

t he

world

suggest

should

they

know

may

be

all

these

used

in

symbols

exam

t hat

questions:

up

to

30%

140/90

have

of

t he

mmHg.

t he

One

condition.

hyper tension

140/90

adult

wit h

population

t hird

One

of

in

dr ugs,

suffers

people

t hree

fail

to

from

sampled

people

keep

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blood

not

are

blood

pressure

know

being

above

t hat

treated

pressure

>

greater

than

≥

greater

than