ATP and Energy Systems

Question 1

What is ATP?

Answer 1

Adenosine Triphosphate, a high energy compound which is the only immediate source of energy for a muscular contraction

Question 2

What molecules create ATP?

Answer 2

1 molecules of adenosine
3 molecules of phosphate
They are chemically bonded

Question 3

What type of reaction is the breakdown of ATP?

Answer 3

An exothermic reaction

Question 4

How is ATP broken down?

Answer 4

The exothermic reaction breaks the chemical bond between the last two phosphates to release chemical energy for muscular contractions

Question 5

How long does ATP energy last?

Answer 5

2-3 seconds

Question 6

What is produced when ATP is broken down?

Answer 6

ADP+P+Energy

Question 7

What is ADP?

Answer 7

Adenosine diphosphate
1 molecule of adenosine and 2 molecules of phosphate, as the other one is broken off in the breakdown of ATP

Question 8

Why does ATP need to be resynthesised?

Answer 8

There is no endless supply

Question 9

How is ATP resynthesised?

Answer 9

Energy is used from an energy store to form a bond between the phosphate molecule and ADP

Question 10

What are the three energy systems?

Answer 10

• ATP-PC system
• Glycolytic system
• Aerobic system

Question 11

What is the ATP-PC system?

Answer 11

ATP is resynthesised from the breakdown of phosphocreatine, the energy produced from the breakdown is used to resynthesise ATP

Question 12

Where does the breakdown of phosphocreatine take place in the ATP-PC system?

Answer 12

In the sarcoplasm (cytoplasm of the muscle cell)

Question 13

What is the catalyst for the breakdown of phosphocreatine in the ATP-PC system?

Answer 13

Creatine kinase, which is released when there is a rise in ADP+P

Question 14

What type of reaction is the resynthesis of ATP?

Answer 14

An endothermic reaction

Question 15

Does the ATP-PC system require oxygen?

Answer 15

No it is anaerobic and provides energy for maximum intensity

Question 16

Why cant the ATP-PC system be used constantly?

Answer 16

The phosphocreatine source is depleted quickly

Question 17

What is the ATP yield in the ATP-PC system?

Answer 17

ATP Yield 1
1 mole of PC : 1 mole of ATP

Question 18

What are the advantages of the ATP-PC system?

Answer 18

• No delay for oxygen
• Phosphocreatine is readily available

Question 19

What are the disadvantages of the ATP-PC system?

Answer 19

• Low ATP yield
• Small PC stores lead to rapid fatigue after 8-10 seconds

Question 20

What is the glycolytic system?

Answer 20

It produces energy when the PC stores been depleted in anaerobic exercise, by using glucose for fuel of resynthesis of ATP

Question 21

What is the enzyme for the breakdown of glucose in the blood and when is it released?

Answer 21

Phosphofructokinase (PFK) is released when ADP+P levels rise

Question 22

What happens when the glucose supply in the body is low, in the glycolytic system?

Answer 22

The body breaks down glycogen using Glycogen Phosphorylase (GPP) to turn it into glucose, maintaining glucose concentration in the blood

Question 23

What happens in anaerobic glycolysis?

Answer 23

Glucose is converted to pyruvic acid and releases energy

Question 24

What enzyme converts glucose to pyruvic acid?

Answer 24

Phosphofructokinase (PFK)

Question 25

What is the ATP yield of the glycolytic system?

Answer 25

ATP yield of 2
1 mol glucose : 2 mol ATP

Question 26

What is a by-product of anaerobic glycolysis and the glycogen system?

Answer 26

Lactic acid

Question 27

Why can’t energy be extracted from pyruvic acid during high intensity exercise? So what happens?

Answer 27

There is no oxygen so lactate dehydrogenase (LDH) converts pyruvic acid to lactic acid

Question 28

What is the effect of lactic acid in the glycolytic system?

Answer 28

• Inhibits enzyme activity and slows the rate of ATP resynthesis
• Fatigue and OBLA

Question 29

What are the stages of the aerobic system?

Answer 29

Aerobic glycolysis
Kreb’s Cycle
Electron transport chain

Question 30

What is aerobic glycolysis?

Answer 30

Pyruvic acid is catalysed by Coenzyme A to produce 2 moles of acetyl CoA

1 mol Glucose : 2 mol Acetly CoA

Question 31

What happens in the Kreb’s cycle?

Answer 31

Acetyl CoA enters the Kreb’s cycle and hydrogen is released and accepted by hydrogen carries NAD and FAD which resynthesises ATP

Question 32

What is the site of the Kreb’s cycle?

Answer 32

Matrix of the mitochondria

Question 33

What is the ATP yield of aerobic glycolysis?

Answer 33

ATP yield of 2
2 mol Acetyl CoA : 2 mol ATP, 2 mol CO2, 2 mol; FADH, 6 mol NADH

Question 34

What happens in the Electron Transport Chain?

Answer 34

NADH and FADH enter the ETC
Hydrogen splits into ions and electrons

Question 35

Where is the ETC located?

Answer 35

The Cristae of the mitochondria

Question 36

What happens to the ions in the ETC?

Answer 36

They are oxidised and removed as water, a by-product

Question 37

What happens to the electrons in the ETC?

Answer 37

They are carried by NAD and release enough energy to resynthesises 34 mol ATP from ADP

Question 38

What is the ATP yield of the aerobic system?

Answer 38

38 mol ATP from 1 mol glucose

Question 39

How do footballers and rugby players save glycogen stores for explosive movements?

Answer 39

Their bodies use fats as fuel for the aerobic system during low intensity exercise.
Lipase breaks down fats into free fatty acids which convert to acetyl COA and enter the Kreb’s cycle