Question

In Krebs cycle, the FAD participates as electron acceptor during the conversion of

• A. succinic acid to fumaric acid
• B. fumaric acid to malic acid
• C. ⍺-­ketoglutarate to succinyl CoA
• D. succinyl CoA to succinic acid

Answer 1

The correct option is A

succinic acid to fumaric acid

The correct option is A.

Explanation for the correct option:

1. Krebs cycle takes place in the mitochondria of the cells.
2. In this process, acetyl CoA present in the mitochondria is oxidized thorough a series of reactions and finally produces water, carbon dioxide and ATP.
3. During Krebs cycle, Flavin Adenine Dinucleotide or FAD gets reduced to FADH₂ during oxidation of succinic acid to fumaric acid.

Explanation for the incorrect options:

Option B:

1. Water participates during the conversion of fumaric acid into malic acid.
2. FAD is not involved in the process.

Option C:

1. NAD⁺ gets reduced to NADH, when ⍺-­ketoglutarate gets converted to succinyl CoA.
2. There is no participation of FAD in this process.

Option D:

1. GDP participates and gets reduced to GTP in the conversion of succinyl CoA to succinic acid.
2. FAD does not participate in this process.

Final Answer: In Krebs cycle, the FAD participates as electron acceptor during the conversion of succinic acid to fumaric acid.