DD - TCA Cycle

Question 1

Why can glycolysis and the TCA cycle all occur in the cytoplasm in prokaryotes?

Answer 1

• Prokaryotes are much smaller and rely on simple diffusion
• Eukaryotic cells rely on compartmentalisation

Question 2

What 5 main things provide evidence for the evolution of mitochondria from symbiotic bacteria?

Answer 2

1. Size and shape
2. Replication through fission
3. Both contain plasmids
4. Similar ribosomes present
5. Both have double membrane structures

Question 3

What part of the mitochondria greatly acts to increase surface area?

Answer 3

Cristae

Question 4

What are the first 4 steps of the TCA cycle?

Answer 4

1. Acetyl-CoA + Oxaloacetate –> Citrate (Water added and CoA recycled)
2. Citrate –> Isocitrate (Tertiary alcohol–> Secondary alcohol)
3. Isositrate → Oxalosuccinate → ɑ-Ketoglutarate (C2 Carboxylated, Carbon lost)
4. ɑ-Ketoglutarate –> Succinyl-CoA (CoA added, Carbon lost)

Question 5

What are the next 4 steps of the TCA cycle?

Answer 5

5. Succinyl-CoA –> Succinate (CoA lost, Substrate-level phosphorylation)
6. Succinate –> Fumarate (FAD reduced)
7. Fumarate –> L-Malate (Hydroxyl added)
8. L-Malate –> Oxaloacetate (NAD reduced)

Question 6

How many ATP is produced in Glycolysis?

Answer 6

8

Question 7

How much net ATP is produced in respiration?

Answer 7

38