Energy Systems

Question 1

How long does the ATP-PC system last? Eg?

Answer 1

10 secs

Eg usian bolt 100m

Question 2

Is the ATP-PC system aerobic or anaerobic?

Answer 2

Anaerobic so there is no oxygen

Question 3

What fuel is used to power ATP resynthesis in the ATP-PC system and where is it stored?

Answer 3

Phosphocreatine

- stored in the muscle cells alongside ATP for rapid access

Question 4

How is phosphocreatine broken down?

Answer 4

1) ATP is used for muscle contraction
1) the increase of ADP and PI releases creatine kinase
2) creatine kinase breaks down PCr into creatine and phosphate
3) energy is released (exothermic) which is used to resynthesis ADP and PI into ATP in the muscle
4) the ATP is broken down for muscle contraction

Question 5

What is the coupled reaction?

Answer 5

As soon as ATP is broken down, the energy from PCr break down resynthesis the ATP

Question 6

What are the three energy systems?

Answer 6

ATP - Pc system
Lactic acid system
Aerobic system

Question 7

What are the advantages of the ATP-PC system?

Answer 7

• ATP can be resynthesised rapidly in mucked cell
• PCr stored are recovered quickly (50=30 secs)
• no fatiguing by products Eh lactic acid

Question 8

What are the disadvantages of the ATP-PC system?

Answer 8

• only available for 10 secs
• PCr replenishment can only take place in the presence of oxygen
• only 1 mole of ATP is resynthesised from 1 mole PCr

Question 9

What is the lactic acid system also known as?

Answer 9

Anaerobic glycolysis

Question 10

How long does the lactic acid system last? Eg

Answer 10

Lasts for around 60 secs

Eg 400m runner

Question 11

What is the energy source for the lactic acid system and where does ATP resynthesis take place?

Answer 11

Glycogen (carbohydrate) stored in the muscle and liver

Takes place in the sarcoplasm in the muscle cell

Question 12

What is the process of lactic acid system?

Answer 12

1) PCr stores run out so glycogen is needed
2) glycogen is converted into glucose-6-phosphate by the enzyme phosophofrutokinase
3) energy is released and makes 2 miles of ATP
4) private acid is produced
5) bc of the lack of oxygen, pyro ate acid is turned into lactic acid by enzyme lactate dehydrogenase

Question 13

What is glycolysis?

Answer 13

Breaking down of glycogen to pyruvate acid by PFK

Question 14

What are the advantages of the lactic acid system?

Answer 14

• doesn’t need the presence of oxygen to work
• lactic acid can be converted back into glycogen and pyruvate in the liver and can be used in the aerobic system
• can be used for sprint finishes / bursts of energy

Question 15

What are the disadvantages of the lactic acid system?

Answer 15

• lactic acid stops energy production as it stops enzymes from working (denatures PFK so glycogen can’t be broken down)
• lactic acid means that intensity must be reduced
• only a small amount of energy can be released

Question 16

What energy source is used in the aerobic system?

Answer 16

Glycogen = 55%
Fats = 30% 
Proteins = 10%

Question 17

When is the aerobic system used? Eg

Answer 17

During rest and moderate intense exercise where oxygen is available

Eg marathon - Mo Farrah

Question 18

What are the 3 stages of the aerobic system?

Answer 18

1) aerobic glycolysis
2) Krebs cycle
3) electron transport chain (ETC)

Question 19

What happens in the first stage of the aerobic system?

Answer 19

1) the glycogen is broken down by PFK into g-6-p and then turns into pyruvate acid
2) bc there is oxygen, pyruvate acid combines with coenzyme A and turns into acetyl coenzyme A
3) now moves from the sarcoplasm to the mitochondria

Question 20

What happens in 2nd stage of aerobic system?

Answer 20

1) it enters the Kreb cycle in the mitrochondria
2) acetyl coenzyme A combined with oxaloacetic to make citric acid
3) the citric acid is oxidised to from hydrogen, carbon dioxide and 2 ATP moles
4) co2 is sent to the lungs and hydrogen is sent to the ETC

Question 21

What happens in the 3rd stage of the aerobic system?

Answer 21

The hydrogen atoms split and give off water and 34 moles of ATP

Question 22

How much more energy is made in the aerobic than anaerobic system?

Answer 22

18 times

36 moles of ATP

Question 23

How are the 3 fuels in the aerobic system used?

Answer 23

Glycogen - glycolysis
Fats - beta oxidisation turns them into fatty acids and then ACoA
Proteins - turns into amino acids and then ACoA

Question 24

What are the advantages of the aerobic system?

Answer 24

• more ATP can be resynthesised
• body has large amount of fat and glycogen so exercise can last for a long time
• doesn’t produce any fatiguing by-products

Question 25

What are the disadvantages of the aerobic system?

Answer 25

• takes a while for sufficient oxygen to become available so can’t be used short term
• fatty acids requires 15% more oxygen in order to break them down into ACoA
• fats can only be broken down in the presence of glycogen. Limited amounts can cause spasm of the muscles