3.1/3 respiration and ATP

Question 1

What is ATP and what is it used for?

Answer 1

A nucleotide that is the energy source in all cells. Used in:
-Active transport
-Cell division
-Nerve transmission

Question 2

What does universal energy currency mean?

Answer 2

It is used for all reactions in all cells in all organisms

Question 3

What is in ATP?

Answer 3

1 ribose
1 adenine
3 phosphate groups

Question 4

Describe ADP to ATP

Answer 4

-Endergonic (takes in energy)
-Condensation
-Catalysed by ATPsynthase

Question 5

Describe ATP to ADP

Answer 5

-Exergonic (releases energy)
-Hydrolysis
-Catalysed by ATPase

Question 6

What are the positives of ATP?

Answer 6

-Only 1 enzyme for breakdown
-Release energy quickly and in small amounts
-Cell can synthesise its own ATP
-If all energy was released, heat would damage cells

Question 7

What are the products of glycolysis? (per glucose)

Answer 7

-2 ATP
-2 NADH
-2 Pyruvate

Question 8

How is ATP produced in anaerobic conditions?

Answer 8

Glycolysis occurs, and pyruvate is converted to lactate, oxidising NADH to NAD

Question 9

What are the products of link reaction? (per glucose)

Answer 9

• 0 ATP
  -2 NADH
  -2 CoA
  -2 CO2

Question 10

What enzymes are used in link reaction?

Answer 10

-Decarboxylase
-Dehydrogenase

Question 11

What are the products of the Krebs cycle? (per glucose)

Answer 11

-2 ATP
- 4 CO2
-6 NADH
-2 FADH2

Question 12

How much ATP can 1 molecule of NADH produce?

Answer 12

3 ATP

Question 13

How much ATP can 1 molecule of FADH2 produce?

Answer 13

2 ATP

Question 14

What are the causes of not reaching maximum yield of ATP?

Answer 14

-Leaky membranes
-Loss of energy as heat
-ATP used for active transport of pyruvate
-Not optimum pH/temp for enzymes

Question 15

Explain why leaky membranes can cause inefficiency

Answer 15

H ions leak through inner mitochondrial membrane instead of going through ATPsynthase and producing ATP

Question 16

What is the role of electrons in chemiosmosis?

Answer 16

They undergo redox reactions whilst being passed through electron carriers, powering H pumps

Question 17

How does cyanide affect chemiosmosis?

Answer 17

Stops flow of electron, preventing it from being accepted by Oxygen, So FADH2 and NADH can’t be oxidised, ATP synthesis will stop

Question 18

What is substrate level phosphorylation?

Answer 18

Enzymes remove high energy phosphate from substrate and directly transfers it to ADP

Question 19

What is oxidative phosphorylation?

Answer 19

Electrons moving through ETC and the production of proton-motive force that drives ATP production

Question 20

What happens to lactate?

Answer 20

-Most is produced in skeletal muscle cells
-Lactate diffuses into blood and taken to hepatocytes (liver)
-Some converted to pyruvate and enters aerobic respiration when Oxygen is available
-Some converted to glycogen and stored

Question 21

What is the plant equivalent of lactate?

Answer 21

Ethanol

Question 22

What is anaerobic respiration in plants called?

Answer 22

Fermentation

Question 23

Explain the respiration of lipids?

Answer 23

-Glycerol enters as Triose Phosphate
-Yields 39 kj/g
-Exact number depends on length of hydrocarbon chain of fatty acid fragments
-When chain is broken down to Acetyl CoA, H is released and picked up by NAD and fed into ETC

Question 24

How is protein respired?

Answer 24

-yield is 17kj/g
-NH2 group removed in liver (deamination)
-Keto-acids enter krebs cycle or glycolysis to form pyruvate

Question 25

What is the equation for the respiratory quotient?

Answer 25

Volume of CO2 out/ Volume of O2 in

Question 26

What is the order for which the food groups would be respired?

Answer 26

1) Carbohydrates
2) Lipids
3) Protein