TCA cylcle

Question 1

What is the fate of the pyruvate and NADH made during glycolysis?

Answer 1

In the absence of oxygen, pyruvate can be reduced to a fermentation product, as NADH is reoxidized to NAD+

Question 2

What happens to pyruvate in the presence of oxygen?

Answer 2

In many organisms, pyruvate is completely oxidized to CO2 by the reactions of the tricarboxylic acid (TCA) cycle, also called the citric acid cycle or the Krebs cycle

Question 3

what is TCA cycle for ?

Answer 3

pathway for the compete oxidation of acetyl-CoA to CO2

Question 4

what does pyruvate dehydrogenase complex task ?

Answer 4

catalyzes the oxidative decarboxylation of Pyruvate to Acetyl-CoA

Question 5

what’s the function and enzymes accompanied with each enzyme that make up the pyruvate dehydrogenase complex?

Answer 5

E1. pyruvate dehydrogenase: pyruvate loses CO2 and HETPP is formed
E2. dihydrolipoyl transacetylase:hydroxyethyl group is transferred to lipoic acid and oxidized to form acetyl dihydrolipoamide.
E3. dihydrolipoyl dehydrogenase: acetyl group is transferred to CoA

Question 6

-ketoglutarate is transaminated to make

Answer 6

glutamate, which can be used to make Arg and Pro plus purine nucleotides

Question 7

Succinyl-CoA

Answer 7

can be used to make porphyrins

Question 8

Fumarate and oxaloacetate

Answer 8

can make several amino acids and also pyrimidine nucleotides

Question 9

Mitochondrial citrate

Answer 9

can be exported to be a cytoplasmic source of acetyl-CoA and oxaloacetate