Q: In the process of pyruvate oxidation, which of the following equations correctly represents the conversion of pyruvate to acetyl CoA?

$$\text{Pyruvate} + \text{NAD}^+ + \text{CoA} \rightarrow \text{Acetyl CoA} + \text{CO}_2 + \text{NADH} + \text{H}^+$$

Question 1

During pyruvate oxidation, which molecule is produced as a result of the removal of a carbon atom from pyruvate?

Accepted Answer

CO$$_2$$

Question 2

What is the primary purpose of adding coenzyme A to the oxidized 2-carbon fragment during pyruvate oxidation?

Accepted Answer

To create a molecule with high potential energy for further breakdown

Question 3

Which of the following best describes the fate of NAD$^+$$ during pyruvate oxidation?

Accepted Answer

It is reduced to NADH

Question 4

In the process of pyruvate oxidation, which of the following equations correctly represents the conversion of pyruvate to acetyl CoA?

Accepted Answer

$$	ext{Pyruvate} + 	ext{NAD}^+ + 	ext{CoA} ightarrow 	ext{Acetyl CoA} + 	ext{CO}_2 + 	ext{NADH} + 	ext{H}^+$$

Question 5

Which of the following statements about acetyl CoA is TRUE?

Accepted Answer

Acetyl CoA contains a high-energy bond due to coenzyme A

Question 6

A patient has a genetic defect in the transport protein responsible for moving pyruvate into the mitochondrion. Which of the following would most likely occur?

Accepted Answer

Pyruvate oxidation would be impaired, leading to decreased acetyl CoA production

Question 7

Which step in pyruvate oxidation directly results in the release of CO$$_2$$?

Accepted Answer

Decarboxylation of pyruvate

Question 8

If a cell is deprived of NAD$$^+$$, what would be the immediate effect on pyruvate oxidation?

Accepted Answer

Pyruvate oxidation would stop because NAD$$^+ is $$required as an electron acceptor

Question 9

Which of the following is NOT a product of pyruvate oxidation?

Accepted Answer

FADH$$_2$$

Question 10

Why is the addition of coenzyme A to the 2-carbon fragment important in cellular respiration?

Accepted Answer

It allows the fragment to enter the citric acid cycle for further energy extraction

Question 11

Which of the following best explains why acetyl CoA has high potential energy?

Accepted Answer

The thioester bond between the acetyl group and coenzyme A stores energy

Question 12

A scientist is studying a mutant cell line that cannot produce coenzyme A. Which process would be directly affected?

Accepted Answer

Formation of acetyl CoA from pyruvate

Question 13

Which of the following is a correct sequence of events during pyruvate oxidation?

Accepted Answer

Transport of pyruvate into mitochondrion, decarboxylation, reduction of NAD$$^+$$, addition of coenzyme A

Question 14

Which of the following would most likely occur if the enzyme responsible for pyruvate oxidation is inhibited?

Accepted Answer

Pyruvate would accumulate in the cytosol

Question 15

In a metabolic disorder where pyruvate cannot be transported into the mitochondrion, which pathway would be upregulated as a compensatory mechanism?

Accepted Answer

Lactic acid fermentation

Pyruvate Oxidation and the Formation of Acetyl CoA

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