Ch12 Anaerobic respiration

Question 1

Lack of O2’s role in halting aerobic respiration

Answer 1

• no final electron acceptor for oxidative phosphorylation
• accumulation of hydrogen
• all FAD and NAD is reduced
• can’t take up H+ from krebs cycle and glycolysis

Question 2

Anaerobic respiration in plants

Answer 2

1. pyruvate bonds with reduced NAD
2. ethanol and CO2 produced
3. NAD is re-oxidised so glycolysis can continue

Question 3

Which organisms have ethanol production

Answer 3

1. yeast
2. root cells under waterlogged conditions

Question 4

Anaerobic respiration in animals

Answer 4

1. pyruvate reacts with NADH
2. produces lactate
3. produces re-oxidised NAD so glycolysis can continue

Question 5

Lactate problem

Answer 5

1. cramps
2. muscle fatigue
3. acidic pH changes which affects enzyme

Question 6

Removal of lactate

Answer 6

1. oxygen debt- oxidising with O2 back to pyruvate(aerobic respiration continues)
2. removed from blood, taken to liver and converted to glycogen

Question 7

Yield of ATP in anaerobic respiraiton

Answer 7

2 molecules

Question 8

Cyanide

Answer 8

1. non-competitive inhibitor of final enzyme in ETC
2. enzyme catalyses addition of e- to O2
3. H+ and e- accumulate on carrier molecules so krebs and ETC stop