Paper 2 Extra 2

Question 1

Difference between blood flowing through pulmonary artery and aorta

Answer 1

blood in pulmonary artery is deoxygenated and has lower pressure

Question 2

How is vena cava different to aorta?

Answer 2

vena cava has lower pressure, deoxygenated blood, greater conc of carbon dioxide and darker red blood

Question 3

What produces progesterone?

Answer 3

Corpus luteum

Question 4

How are blood cells adapted?

Answer 4

The blood vessel has thick walls/small lumen to carry oxygenated blood under high pressure.

Question 5

What does oestrogen inhibit?

Answer 5

FSH

Question 6

What sticks out of hairs?

Answer 6

Sebaceous

Question 7

What does low progesterone cause?

Answer 7

FSH to be released

Question 8

Function of stomata

Answer 8

Gas exchange and for water vapour to leave

Question 9

What is top layer

Answer 9

Upper epidermis

Question 10

difference between normal leaf and xerophyte?

Answer 10

leaf becomes a spine / reduced
surface area (1)
• (waxy) cuticle is thicker (1)
• stomata are sunk in pits / fewer
stomata /smaller stomata (1)
• leaf is rolled / curled leaves(1)
• guard cells / stomata close during the
day

Question 11

Describe the route taken by urine from the kidney until it leaves the body

Answer 11

(travels from the kidneys) through the ureters (1)
• to the bladder (where it is stored)(1)
• (from the bladder) through the urethra (and out of the body

Question 12

Where are amino acids broken down into urea?

Answer 12

The liver.

Question 13

Where do ova mature?

Answer 13

In the follicles

Question 14

Why does the corpus luteum produce progesterone around day 20?

Answer 14

To maintain the lining of the uterus

Question 15

Explain why taking high levels of oestrogen and progesterone in the combined
contraceptive pill reduces the chance of pregnancy

Answer 15

to inhibit the production of FSH
(1)
• to prevent eggs maturing (1)
OR
• to inhibit the production LH (1)
• so ovulation is prevented (1)

Question 16

What diffuses with alveoli ?

Answer 16

Capilaries

Question 17

Are arteries wide/

Answer 17

No

Question 18

Are veins wide?

Answer 18

Yes.

Question 19

Explain why there are differences in the concentrations of some components
in the blood and some components in this part of the nephron.

Answer 19

{red blood cells/ white blood cells / proteins} {are
not present in the filtrate / cannot be filtered into
the nephron} (1)
• because they are too large to pass {through the
membrane/into the nephron} (1)
OR
• glucose is found in the filtrate (1)
• because it is small enough to pass {through the
membrane / into the nephron} (1)

Question 20

Why is a coverslip used to place on top of the leaf?

Answer 20

keep leaf peel flat (1)
• keep leaf peel in place (1)
• protect the (objective) lens (1)
• protect the specimen (1)

Question 21

explain why the leaf peel rather than the whole leaf was viewed with a microscope

Answer 21

the leaf peel is thin / leaf is too
thick (1)
• as the leaf peel allows light to
pass through it/the leaf would
not allow light to shine through it
(1)
• to enable the {stomata / cells/
guard cells} to be identified (1)

Question 22

How do guard cells take in water?

Answer 22

Through osmosis.

Question 23

Explain why it is an advantage to the plant to have this distribution of stomata
in the upper and lower surfaces of the leaf.

Answer 23

• no stomata (in the upper
surface) to reduce water
loss (1)
• water loss during
transpiration /
evaporation (1)
OR
• stomata (on the lower
surface) allow gas
exchange (1)
• gas exchange is needed
for photosynthesis (1)

Question 24

) Explain why there is a change in the rate of blood flow through the digestive
system during exercise.

Answer 24

there is increased blood flow to
the muscles (1)
• to allow for { respiration/
release of energy} (in the
muscles) (1)

Question 25

The stroke volume is the amount of blood leaving one chamber of the heart per beat. From which chamber of the heart does this volume of oxygenated blood flow?

Answer 25

Left ventricle

Question 26

When an iguana is too hot, it pants by opening its mouth to cool down. Explain how this behaviour helps to cool the iguana down.

Answer 26

• (panting) causes water loss (1) • causing evaporation / removal of latent heat (so reduction in temperature)

Question 27

) Explain the role of vasodilation in thermoregulation

Answer 27

``` vasodilation acts to cool the body down (1) • more blood flows near the surface of the skin (1) • less blood flows through the shunt valve (1) • causing increased thermal energy loss ( ```

Question 28

Transpiration

Answer 28

* the movement of water * from the root through the plant * through the lignified cells/dead cells * of the xylem * driven by evaporation of water from the leaves * through the stomata * flow is only in one direction * by capillary action * according to the cohesion-tension theory

Question 29

Translocation

Answer 29

``` the movement of sugars from the leaves • through the plant • as sucrose • through the living sieve cells • of the phloem • flow is bidirectional • to sinks in the plant where the sucrose is needed ```

Question 30

Explain how clomifene therapy may increase the chance of a woman over the age of 50 becoming pregnant.

Answer 30

``` causes the release of FSH (1) • stimulating eggs to develop (in the follicles/ovary) (1) OR • causes the release of LH (1) • stimulating ovulation (1) ```

Question 31

Explain how the release of adrenalin can result in the improved performance of an athlete.

Answer 31

``` adrenalin acts to increase heart rate / blood pressure (1) • so there is increased blood flow (1) • causes the release of glucose from glycogen (1) • so increased {oxygen/glucose} (1) • increased the rate of respiration (1) • to release energy (for the working muscles/body) (1) ```

Question 32

Variables auxins

Answer 32

Direction of light.

Question 33

Grass flexible

Answer 33

So does not break in windy conditions

Question 34

why is leaf rolled

Answer 34

to trap air inside

Question 35

what does stomata cause

Answer 35

Water loss

Question 36

What do hairs on lower surface do

Answer 36

Reduce air movement