Biochem- TCA CYCLE And Glycogen Metabolism

Question 1

Define the TCA Cycle.

Answer 1

The TCA Cycle is the final common oxidative pathway for carbohydrates, fats and amino acids.

Question 2

What is the site of the TCA Cycle

Answer 2

Mitochondrial matrix

Question 3

In the TCA Cycle, the oxidation of what occurs?

Answer 3

Acetyl CoA —> CO2 and H2O

Question 4

The reactions concerned to replenish the intermediates of the TCA Cycle is known as _________________.

Answer 4

Anaplerosis or anaplerotic rxns.

Question 5

In which three steps of the TCA Cycle is the 3 NADH is produced?

Answer 5

1 isocitrate —> alpha- ketoglutarate
2. A- ketoglutarate —> succinyl- CoA
3. Malate —> Oxaloacetate

Question 6

What is the rate limiting enzyme of the TCA Cycle?

Answer 6

Isocitrate Dehydrogenase

Question 7

What stimulates the TCA Cycle?

Answer 7

ADP

Question 8

What is the main goal of the TCA Cycle?

Answer 8

Generate 3 NADH and 1 FADH2

Question 9

Explain how the TCA Cycle contributes to the production of ATP.

Answer 9

With the presence of ADP, ADP stimulates the TCA Cycle.
To produce ATP, the electron transport chain is required. The TCA cycle produces NADH and FADH2 which is needed by the electron transport chain to produce ATP.

Question 10

What inhibits the TCA cycle?

Answer 10

ATP
NADH
FADH

Question 11

List the enzymes that catalyze the TCA Cycle

Answer 11

Citrate Synthase
Aconitase
Isocitrate dehydrogenase
Alpha- ketoglutarate dehydrogenase
Succinate thiokinase
Succinate dehydrogenase
Fumarase
Malate dehydrogenase

Question 12

Which rxn is FADH2 produced?

Answer 12

Succinate — Fumerase

Question 13

What step of the TCA cycle is catalyzed by the rate limiting enzyme?

Answer 13

Isocitrate — A- ketogluterate.

Question 14

Define glycogenesis

Answer 14

Synthesis glycogen from glucose which occurs in the liver and muscle.