Human Cells Unit 1 KA 8

Question 1

What happens to Pyruvate during vigorous exercise?

Answer 1

During vigorous exercise, pyruvate is converted to lactate as there isn’t sufficient oxygen

Question 2

What happens during Gylcolysis in Anaerobic respiration?

Answer 2

Glucose is broken down to Pyruvate, which is converted to Lactate

Question 3

What does the conversion of Pyruvate -> Lactate involve?

Answer 3

The conversion of pyruvate -> lactate involves the transfer of hydrogen from NADH produced during Glycolysis
This regenerates NAD which is needed to maintain ATP production

Question 4

What happens when Lactate accumulates?

Answer 4

When lactate accumulates, muscle fatigue occurs

Question 5

When is oxygen debt repaid?

Answer 5

Oxygen debt is repaid when exercise is complete, this allows respiration to provide the energy to convert lactate back to pyruvate and glucose in the liver

Question 6

What are the two types of Muscle fibres?

Answer 6

1) Slow-twitch
2) Fast-twitch

Question 7

Describe Slow-twitch muscle fibres - (8)

(contraction speed/time, fatigue speed, pathway, mitochondria num, blood supply, myoglobin concentration, storage fuel)

Answer 7

1) Slow contraction speed
2) Long contraction time
3) Slow fatigue speed
4) Aerobic Respiration
5) Many mitochondria
6) Large blood supply
7) High concentration of myoglobin
8) Storage fuel - fats

(Long distance running)

Question 8

Describe Fast-twitch muscle fibres - (8)

(contraction speed/time, fatigue speed, pathway, mitochondria num, blood supply, myoglobin concentration, storage fuel)

Answer 8

1) Fast contraction speed
2) Short contraction time
3) Fast fatigue speed
4) Glycolysis
5) Few mitochondria
6) Small blood supply
7) Low concentration of myoglobin
8) Storage fuel - Glycogen/ Creatine phosphate

(Sprinting - bolt)

Question 9

What is Anaerobic respiration?

Answer 9

Respiration that occurs without oxygen

Question 10

What is Aerobic respiration?

Answer 10

Respiration that occurs with oxygen