3.4

Question 1

Veins vs Artery in transporting blood

Answer 1

1) Veins transport blood towards the heart
2) Artery transport blood away from the heart

Question 2

3 types of blood vessels

Answer 2

Ateries
Veins
Capillaries

Question 3

Describe and explain function of arteries [4]

Answer 3

1) Carry blood away from your heart to your organ
2) Arteries can stretch (Pulse)
3) Blood in arties is under high pressure
4) Arties have a small lumen with thick elastic walls to handle the high blood pressures.

Question 4

Describe and explain veins [4]

Answer 4

1) Carry blood back to your heart
2) No pulse
3) Contains valves that prevent back flow of blood
3) Blood is squeezed back towards the heart by the action of the skeletal muscles
4) Large lumen and relatively thin walls as bloodpressure is lower

Question 5

Describe and explain functions of calliparies

Answer 5

1) Form a huge network linking arteries and veins
2) Allows blood to access every cell in our body
3) Walls are only 1 cell thick, reducing diffusion distance (Allows diffusion)

Question 6

Blood vessels in livers[3]

Answer 6

1) The hepatic artery carries oxygenated blood to the liver
2) The hepatic vein carries deoxygenated blood back to the heart
3) The hepatic portal vein carries nutrient-rich blood from the intestines to the liver
4) Hepatic = always to do with the liver

Question 7

Blood vessels in the kidneys [3]

Answer 7

1) Oxygenated blood is carried to the kidneys in the renal artery
2) Deoxygenated blood is carried back to the heart in the renal vein
3) Renal = always to do with the kidney

Question 8

Define circulatory system

Answer 8

System of blood vessels with a pump and valves to ensure one-way flow of blood

Question 9

Explain the advantages of a double circulation [3]

Answer 9

1) Blood circulating the lung is at low blood pressure
2) Pressure can raised again by pumping blood back to the heart
3) Ensures blood pressure is high enough to travel all across the body

Question 10

Describe the single circulation of fish [2]

Answer 10

1) 2 chambered heart
2) Blood passes through the heart once per heart beat (Once per circulation cycle)

Question 11

Describe the double circulation of mammal [2]

Answer 11

1) 4 chamber heart
2) Blood passes through heart twice per cycle

Question 12

Describe the advantages of having a double circulation system [2]

Answer 12

1) Blood moves slowly in the lung to absorb as much oxygen as possible
2) Blood have higher pressure to pump blood into cells as fast as possible

Question 13

How can the activity of a heart be monitored? [3]

Answer 13

1) using an ECG
2) measuring pulse rate
3) listening to the sounds of valves closing using a stethoscope

Question 14

Investigate and describe the effect of physical activity on the heart rate [5]

Answer 14

1) Pulse rate or breathing rate can be used as dependent variable while exercising length or type is used for IV
2) Take a resting pulse
3) Exercise for 2 minutes and immediately take pulse
4) rest for 3 minutes to return pulse to resting
5) Repeat step 3-4 and calculate average

Question 15

RIsk factors of coronary heart disease (CHD) [6]

Answer 15

1)) diet
2) Lack of exercise
3) Stress
4( Smoking
5) Genetic predisposition
6) Age & sex

Question 16

Describe coronary heart disease (How it occurs)[3]

Answer 16

1) Caused by the blockage of coronary arteries
2) May be blocked by plague
3) Coronary artery narrows, restricting blood flow so heart attack may occur

Question 17

Reducing the risks of developing coronary heart disease

Answer 17

1) Quit smoking
2) Diet - reduce animal fats and eat more fruits and vegetables - this will reduce cholesterol levels in the blood and help with weight loss
3) Exercise regularly - weight loss, decrease blood pressure and cholesterol levels and help reduce stress

Question 18

Explain the relative thickness of the muscle walls of the left and right ventricles [2]

Answer 18

1) The left ventricle wall is thicker because it pumps blood in high pressure
2) right ventricle pump blood at lower pressure

Question 19

Explain the relative thickness of the muscle walls of the astria compared to those of the ventricle

Answer 19

The ventricles have thicker muscle walls than the atria as they are pumping blood out of the heart and so need to generate a higher pressure

Question 20

Explain importance of the septum

Answer 20

separates the two sides of the heart and so prevents mixing of oxygenated and deoxygenated blood

Question 21

Describe the functions of the heart in action [6]

Answer 21

1) Deoxygenated blood coming from the body flows into the right atrium
2) Once the right atrium has filled with blood the heart gives a little beat and the blood is pushed through the valve into the right ventricle
2) The walls of the ventricle contract and the blood is pushed into the pulmonary artery through the semilunar valve which prevents blood flowing backwards into the heart
3) The blood travels to the lungs and oxygen-rich blood returns to the left atrium via the pulmonary vein
4) It passes through the atrioventricular valve into the left ventricle
5) The thicker muscle walls of the ventricle contract strongly to push the blood forcefully into the aorta and all the way around the body
6) The semilunar valve in the aorta prevents the blood flowing back down into the heart

Question 22

Explain the effect of physical activity on the heart rate

Answer 22

1) blood is taken to the working muscles to provide them with enough nutrients and oxygen for increased respiration
2) An increase in heart rate also allows for waste products to be removed at a faster rate
3) Following exercise, the heart continues to beat faster for a while to ensure that all excess waste products are removed from muscle cells
4) It is also likely that muscle cells have been respiring anaerobically during exercise and so have built up an oxygen debt
5) This needs to be ‘repaid’ following exercise and so the heart continues to beat faster to ensure that extra oxygen is still being delivered to muscle cell
6) The extra oxygen is used to break down the lactic acid that has been built up in cells as a result of anaerobic respiration

Question 23

Blood 4 main components

Answer 23

red blood cells, white blood cells, platelets and plasma

Question 24

Identifying red vs white blood cells

Answer 24

Red blood cells have a concave disc shape with no nucleus
White blood cells are usually round in shape with a nucleus

Question 25

Plasma function

Answer 25

transport of carbon dioxide, digested food (nutrients), urea, mineral ions, hormones and heat energy

Question 26

Red blood cell function

Answer 26

transport oxygen around the body from the lungs to cells which require it for aerobic respiration
They carry the oxygen in the form of oxyhaemoglobin

Question 27

White blood cells

Answer 27

defend the body against infection by pathogens by carrying out phagocytosis and antibody production

Question 28

Platelets

Answer 28

helping the blood to clot

Question 29

Why is blood clotting important

Answer 29

Prevent blood loss and entry of pathogens

Question 30

lymphocytes

Answer 30

Antibody production

Question 31

Phagocytes

Answer 31

Engulfing pathogens by phagocytosis

Question 32

Lymphocytes vs phagocytes in diagram

Answer 32

Lymphocytes are rounder
Phagocytes is built weird

Question 33

Describe Blood clotting process [3]

Answer 33

1) Blood clot is the accumulation of platelets on an open wound
2) Platelets form an insoluble mesh and a hardened scab over a wound
3) Blood clot prevent blood loss and entry of pathogens

Question 34

Blood clot explained [2]

Answer 34

1) Platelets release chemicals that cause soluble fibrinogen proteins to convert into soluble fibrin and form an insoluble mesh across the wound, trapping red blood cells and therefore forming a clot
2) The clot eventually dries and develops into a scab to protect the wound from bacteria entering