Energy Systems in Muscle Cells: Key Area 1.8

Question 1

What does creatine phosphate do?

Answer 1

Breaks down to release energy and phosphate, which are used to convert ADP to ATP at a fast rate

Question 2

How fast does creatine phosphate run out in muscle cells?

Answer 2

Around ten seconds

Question 3

When is creatine phosphate levels restored?

Answer 3

When energy demand on muscle cells is low

Question 4

In what conditions is pyruvate formed in glycolysis converted to lactic acid?

Answer 4

Oxygen deficient conditions

Question 5

What does lactic acid build up in muscle cells cause?

Answer 5

Fatigue and oxygen debt

Question 6

How can oxygen debt be repaid?

Answer 6

In a recovery period following strenuous exercise, during which time lactic acid is broken down.

Question 7

What contracts to bring about the movements of strenuous exercise?

Answer 7

Skeletal muscle

Question 8

What two twitches does skeletal muscle have?

Answer 8

Slow twitch fibres and fast twitch fibres

Question 9

Describe slow twitch fibres.

Answer 9

They contract more slowly but can sustain contractions for longer and are effective for endurance activities

Question 10

Describe fast twitch fibres.

Answer 10

Dhsh contract more quickly over short periods and are effective for short bursts of strenuous activity.