Part 2: The Response To Exercise

Question 1

Describe how muscle contractions change during exercise and why. (3)

Answer 1

1. Contract harder and faster
2. Enables you to move faster
3. Enables toy to move heavier things

Question 3

Describe how glycogen stores change during exercise and why. (2)

Answer 3

1. Broken down into glucose
2. So we can respire (glucose is the substrate for aerobic and anaerobic respiration).

Question 4

Describe how heart rate changes during exercise and why. (3)

Answer 4

1. Increases
2. To pump more oxygen and more glucose to the muscles
3. To get rid of more carbon dioxide

Question 5

Describe how arteries supplying muscles with blood change during exercise and why. (3)

Answer 5

1. They widen
2. To supply more blood to the muscles.
3. Therefore more glucose and more oxygen.

Question 6

Describe how breathing rate and depth of breathing change during exercise and why. (2)

Answer 6

1. They increase
2. Greater supply of oxygen for aerobic respiration and also remove more carbon dioxide.

Question 7

Explain how the recovery phase would be different if an unfit person exercised. (4)

Answer 7

1. Produce more lactic acid
2. Therefore, they need more oxygen to break down lactic acid.
3. Their lungs are less efficient (diaphragm/intercostal muscles less ‘fit’).
4. So it takes longer to pay off the oxygen debt.

Question 8

State how the volume of the heart at rest changes as a result of long-term exercise and why this is beneficial. (4)

Answer 8

1. It increases
2. Each beat can pump more blood
3. So delivers more oxygen and glucose
4. So more aerobic respiration takes place.

Question 9

State how the volume of blood pumped by each heartbeat changes as a result of long-term exercise and why this is beneficial. (4)

Answer 9

1. It increases
2. More oxygen and glucose pumped to the muscles
3. As the heart doesn’t need to beat as often.
4. Puts less strain on the heart.

Question 10

State how the resting pulse/heart rate changes as a result of long-term exercise and why this is beneficial. (3)

Answer 10

1. It decreases
2. Less strain on the heart
3. Not working as hard.

Question 11

State how the maximum lung volume changes as a result of long-term exercise and why this is beneficial. (3)

Answer 11

1. It increases
2. The lungs take in more oxygen with each breath
3. And get rid of more carbon dioxide.

Question 12

State how the resting breathing rate changes as a result of long-term exercise and why this is beneficial. (3)

Answer 12

1. It decreases
2. Less strain on the lungs/ribcage
3. Because they’re not working too hard.

Question 13

Explain why a fitter person produces less lactic acid after hard exercise than an unfit person. (4)

Answer 13

1. Larger and stronger heart, plus longer lung capacity
2. Means they deliver more oxygen to muscles
3. Therefore more aerobic respiration and less anaerobic respiration.
4. Less lactic acid produced

Question 14

Explain why a fitter person cam pay off their oxygen debt quicker than an unfit person. (3)

Answer 14

1. Larger lung capacity
2. Means can get more oxygen per breath to break down lactic acid more quickly in the liver
3. Less lactic acid to break down in the first place.