5.3 Energy Transfer during short duration/high intensity exercise

Question 1

how does the ATP-PC system synthesize ATP

Answer 1

• ATP is broken down by ATPase
• this enzyme will break the last bond between the phosphates which will release energy and break ATP into ADP + P + energy

Question 2

what is ATP

Answer 2

• adenosine triphosphate
• the biological currency of the body
• all cellular metabolic reactions are powered by ATP

Question 3

what occurs when ATP levels are low

Answer 3

creatine kinase is activated

phosphocreatine is broken down by creatine kinase and the phosphate molecule is used to resynthesize to reproduce ATP

Question 4

what is the ATP-PC system known as

Answer 4

a couple reaction (one reaction has to happen for the other)

Question 5

what is the fuel for the ATP-PC system

Answer 5

phosphocreatine

Question 6

what is the site of the ATP-PC reaction

Answer 6

sarcoplasm

Question 7

what is the enzyme used in the ATP-PC system

Answer 7

creatine kinase, ATPase

Question 8

what is the yield in the ATP-PC system

Answer 8

1:1

Question 9

what are the advantages of the ATP-PC system

Answer 9

• high intensity
• no harmful by products
• no delay in oxygen delivery
• anaerobic

Question 10

what are the disadvantages of the ATP-PC system

Answer 10

• 10s (short duration)
• inefficient (low energy yield)

Question 11

what is the work to rest ratio of the ATP-PC system

Answer 11

1:10-12 (for every 1 sec of work you need 10-12 sec of recovery)

Question 12

quick recap of the ATP-PC system

Answer 12

• anaerobic
• muscle cell has a small amount of ATP to use immediately and phosphocreatine
• lasts for 10s
• if exercise continues at a high intensity the PC store is only partially replenish as there is not enough energy available to reform phosphocreatine

Question 13

exam question answer to the ATP-PC system

Answer 13

This system can supply energy for anaerobic activity over a very short period of time –up to 10 seconds. Muscles have a store of phosphocreatine which can be readily broken down in to creatine and phosphate. This breakdown results in one molecule of ATP being produced. Phosphocreatine is extremely limited, hence why a time limit of 10 seconds of intense exercise is present.

Question 14

what is the other anaerobic system

Answer 14

anaerobic glycolysis system

Question 15

how long does anaerobic glycolysis last for

Answer 15

10s - 3mins depending on the intensity

Question 16

what is the process of anaerobic glycolysis

Answer 16

• muscle/liver glycogen in broken down to glucose by glycogen phosphorylase
• then glucose is broken into pyruvic acid and 2 ATP by phosphofructokinase

Question 17

what occurs in anaerobic glycolysis when not enough oxygen is present

Answer 17

lactic acid (produced by lactate dehydrogenase)

Question 18

when is the anaerobic glycolysis system activated

Answer 18

when the ATP-PC system fades - activated by low levels of phosphocreatine

Question 19

what occurs if lactic acid is accumulated

Answer 19

it diffuses into the tissue fluid and blood, if not removed quickly it builds up to impede muscle contraction and causes fatigue

Question 20

how long is recovery time for the anaerobic glycolysis system

Answer 20

approx 8 mins

Question 21

advantages of the anaerobic glycolysis system

Answer 21

• high intensity
• no delay in oxygen delivery
• ATP can be resynthesized quickly due to few chemical reactions
• it can be easily used for a sprint finish

Question 22

what are the disadvantages of anaerobic glycolysis

Answer 22

• short duration
• by product of lactic acid
• energy yield 1:2

Question 23

image of the anaerobic glycolytic system

Answer 23