Krebs Cycle

Question 1

Where does the Krebs Cycle occur?

Answer 1

in mitochondria

Question 2

Are all substances in Krebs cycle completely oxidized?

Answer 2

If we need aspartate, we can pull off Oxaloacetate, when we need glutamate, we pull off from ketoglutarate. When we need porphyrins (heme, hemoglobin) we will pull off from Succinyl CoA

Question 3

What is the beginning step in the Krebs cycle?

Answer 3

Acetyl CoA from Pyruvate combines with oxaloacetate by catalyst citrate synthase to create Citrate

Question 4

What surplus end products inhibit the Krebs cycle?

Answer 4

ATP, NADH, Succinyl CoA

Question 5

What activates the Krebs cycle?

Answer 5

ADP

Question 6

What are the 4 possible fates of oxaloacetate?

Answer 6

1. Condensation with acetyl CoA to form citrate
2. Conversion into glucose via the gluconeogenic pathway
3. Conversion into pyruvate
4. Transamination to aspartate

Question 7

Describe the anapldrotic process in restoring oxaloacetate to the Krebs cycle?

Answer 7

pyruvate carboxylase is regulated positively by Acetyl CoA to form oxaloacetate from pyruvate, which accelerates the filling up process, restoring oxaloacetate to the cycle

Question 8

What does the Krebs cycle start and end with?

Answer 8

Oxaloacetate

Question 9

what is the single most impotent mechanism for ensuring an ample supply of oxaloacete?

Answer 9

The reaction by which oxaloacetate is directly formed from pyruvate by pyruvate carboxylase with help of biotin