Question

The Krebs cycle takes place in the mitochondria of cells when adequate oxygen is present. Which substance is a product of the Krebs cycle?

Answer 1

The Kreb's cycle has three products:

1. ATP
2. Carbon dioxide
3. Energy yielding compounds (NADH and FADH2)

Step-by-step explanation:

Each glucose molecule that enters glycolysis is converted into 2 molecules of pyruvate. For each pyruvate, the products and respective pathways of Kreb's cycle are:

• Pyruvate dehydrogenase converts pyruvate to Acetyl CoA producing 1 molecule of NADH per pyruvate oxidized.

• In Kreb's cycle, isocitrate dehydrogenase, alpha-ketoglutarate dehydrogenase, and malate dehydrogenase reactions produce 1 molecule of NADH each.
• Succinate dehydrogenase reaction produces a single molecule of FADH2 per FAD reduced.
• The conversion of succinyl Co-A into succinate by the enzyme succinyl Co-A synthetase produces 1 ATP per pyruvate.

• Since, 2 molecules of pyruvate enter the Kreb's cycle, all the products will be multiplied by 2. Therefore, the final products of the Kreb's cycle are:

• 2 ATP
• 4 CO2
• 6 NADH
• 2 FADH2