Understand pyruvate decarboxylation

Help Questions

AP Biology › Understand pyruvate decarboxylation

Questions 1 - 6
1

Which is not a product of pyruvate decarboxylation reaction?

acetyl

Explanation

The pyruvate decarboxylation reaction is pyruvate+ CoA-SH+ NAD+ -> NADH+ CO2+ acetyl CoA.

2

For each glucose molecule that undergoes glycolysis, how many acetyl CoA molecules are produced at the end of pyruvate decarboxylation?

2

1

4

32

Explanation

During glycolysis, for each molecule of glucose, two molecules of pyruvate are produced ( glucose+ NAD+ + 2 ADP + 2Pi-> 2 pyruvate+ 2 ATP + 2NADH+. These 2 molecules of pyruvate then undergo the pyruvate decarboxylation reaction: 2(pyruvate+ CoA-SH+ NAD+ -> NADH+ CO2+ acetyl CoA).

3

During pyruvate decarboxylation reaction, pyruvate is converted to _______________ compound, through a reaction called ______________ .

acetyl CoA; oxidative decarboxylation

acetyl CoA; reductive decarboxylation

NADH; oxidative decarboxylation

ATP; decomposition

Explanation

Pyruvate decarboxylation is an oxidative decarboxylation reaction, or an oxidation reaction where a carboxylate group is removed. This reaction converts pyruvate which was produced through glycolysis to acetyl CoA to be used in the Citric Acid Cycle.

4

During the pyruvate decarboxylation reaction, acetyl CoA is produced through which type of bond linking an acetyl group to coenzyme A?

hydrogen bond

ionic bond

thioester bond

acetylase bond

Explanation

During the pyruvate decarboxylation reaction , a thioester bond links the acetyl group of pyruvate with coenzyme A to produce acetyl CoA.

5

Where does the pyruvate decarboxylation reaction occur?

Cytosol

Mitochondrial matrix

Cristae

Outer mitochondrial membrane

Explanation

Pyruvate decarboxylation occurs in the mitochondrial matrix. The acetyl CoA produced from the pyruvate decarboxylation reaction will undergo the Citric Acid cycle also in the mitochondrial matrix.

6

Which enzyme complex catalyzes the pyruvate decarboxylation reaction?

pyruvate reductase

pyruvate dehydrogenase complex

pyruvate oxidase

acetyl dehydrogenase

Explanation

The pyruvate dehydrogenase complex is an enzyme complex that consists of 3 enzymes, which work together to catalyze the pyruvate decarboxylation reaction, where pyruvate is converted to acetyl CoA.

Return to subject