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Question 1

What type of circulatory system is the heart.

Answer 1

Double circulatory system

Question 2

Where is blood pumped away in the heart?

Answer 2

Aorta

Question 3

Why does blood slow down at the capillaries?

Answer 3

Capillaries are much smaller then the arteries.

Slower movement allows for gas exchange.

Question 4

How does the vein prevent blood backflow?

Answer 4

Has valves

Question 5

What is the problem of a single circulatory system?

Answer 5

Blood loses a lot of pressure meaning that blood travels to organs very slowly so it cant deliver a lot of oxygen.

Question 6

What is the benefit of a double circulatory system?

Answer 6

Because it pumps through the heart twice, blood travels faster meaning it can deliver oxygen needed to cells.

Question 7

What are the heart’s 4 chambers?

Answer 7

Right atrium

Left Atrium

Right ventricle

Left ventricle

Question 8

How is blood transferred around the body?

Answer 8

The vena cava brings in deoxygenated blood from the body.

The blood passes from the heart to the lungs in the pulmonary artery.

In the lungs the blood collects oxygen.

Oxygenated blood passes from the lungs to the heart in the pulmonary vein.

Oxygenated blood is pumped from the heart to the body in the aorta.

Question 9

What are the veins that branch out from the aorta and spread to the heart muscle?

Answer 9

Coronary artery

Question 10

What is the purpose of the coronary arteries?

Answer 10

To provide oxygen to the muscle cells of the heart.

The oxygen is used in respiration to provide the energy for contraction

Question 11

What controls the resting heart rate?

Answer 11

The pacemaker

Question 11

What controls the resting heart rate?

Answer 11

The pacemaker

Question 12

What is the use of a artificial pacemaker?

Answer 12

An artificial pacemaker is a small electrical device and it corrects irregularities in the heart rate.

Question 13

Describe 3 ways mitosis occurs.

Answer 13

Growth

Replacing cells

Repairing tissues

Question 14

Explain 3 stages of the cell cycle?

Answer 14

Stage 1 - The cell grows, DNA is made into copies and more organelles are made.

Stage 2 - Mitosis in which the nucleus divides inside the cell

Stage 3 - The cell splits into two identical daughter cells

Question 15

What are the functions of meristems in plants?

Answer 15

It can differentiate to any type of plant.

Question 16

Some athletes train at high altitude.

Training at high altitude increases the number of red blood cells per cm3 of blood.

Explain why having more red blood cells per cm3 of blood is an advantage to an athlete

Answer 16

More haemoglobin. (1)

(therefore) more oxygen can be carried / transported. (1)

(for) more (aerobic) respiration of muscle (cells).

Accept more energy released for muscle (cells).

Question 17

The data was collected over 15 years and 400 patients were involved.

Use information from the table above and your own knowledge to answer the following question.

A patient decides to have a mechanical valve replacement rather than a pig tissue valve replacement.

Suggest reasons for and against choosing a mechanical valve.

Answer 17

Reasons for: any two of the following
* Less likely to die (44% cf. 59%)
* Lower risk of death from having a second operation
* Lower risk of heart infections
* Less chance of the valve stopping working
* Longer lasting
* Doesn’t cause rejection
* Avoids religious issues of using organs from a pig or no
* Ethical issue from using part of a living organism.

Reasons against: any two of the following
* Chance of death by bleeding is increased
* Offers no advantage against clots or equal risk of blood clots
* have to take anti-clotting drugs for life
* can be noisy.

Question 18

Which two blood vessels carry deoxygenated blood?

Answer 18

Vena cava

Question 19

Compare the structure of an artery with the structure of a vein.

Answer 19

Arteries have a thicker layer of muscle (tissue) or veins have a thinner
layer of muscle (tissue). (1)

Arteries have a thicker layer of elastic tissue or veins have a thinner
layer of elastic tissue. (1)

Arteries have a narrower lumen or veins have a wider lumen.
Allow descriptions of ‘lumen’. (1)

Arteries do not have valves and veins have valves.
Allow only veins have valves

Question 20

A patient may be fitted with an artificial pacemaker.

What condition may be treated using an artificial pacemaker?

Answer 20

An irregular heartbeat.

Question 21

The circulatory system transports substances such as glucose and oxygen around
the body.

a. Name three other substances that the circulatory system transports around the body.

Answer 21

Any three from:

Carbon dioxide / CO2 (1)
Urea (1)
Protein (1)
Water / H2O (1)
Hormones / insulin

Question 22

Blood is a tissue. Blood contains red blood cells and white blood cells.

Name two other components of blood.

Answer 22

Platelets

Plasma

Question 23

A comparison is made between blood taken from an artery in the leg and blood taken from a vein in the leg.

Give two differences in the composition of the blood.

Answer 23

Any two from:
(artery has) more oxygen (1)
(artery has) more glucose (1)
(artery has) less carbon dioxide (1)
(artery has) less lactic acid

Question 24

How is the leaf tissue adapted to photosynthesis?

Answer 24

Waxy cuticle is transparent so sunlight can pass through.

The waxy cuticle is 1 cell thick so that diffusion is more efficient

Next layer is packed with chloroplast - photosynthesis takes place

Next layer consists of spongy cells which have air gaps that allow more oxygen and carbon dioxide to diffuse in and out.

Xylem helps with transporting water throughout the plan,

Guard cells open and close so that gases can enter and leave the plant