Question

during which stage of cellular respiration is glucose broken down into two molecules of pyruvic acid?
○ electron transport chain
○ glycolysis
○ krebs cycle
○ acetyl coa formation

Explanation:

To solve this, we analyze each stage:

• Electron transport chain: Involves ATP production via electron transfer, not glucose breakdown.
• Glycolysis: The first stage of cellular respiration where one glucose molecule is broken down into two pyruvic acid (pyruvate) molecules.
• Krebs cycle: Uses acetyl - CoA (derived from pyruvate) to produce energy - carrying molecules, not the initial glucose breakdown to pyruvate.
• Acetyl CoA formation: Converts pyruvate (from glycolysis) to acetyl - CoA, not the breakdown of glucose to pyruvate.

Answer:

B. glycolysis