Question

question 14 (1 point)
in which order do the stages of aerobic cellular respiration occur?
○ citric acid cycle, glycolysis, electron transport chain, pyruvate oxidation.
○ glycolysis, citric acid cycle, electron transport chain, pyruvate oxidation.
○ glycolysis, citric acid cycle, pyruvate oxidation, electron transport chain.
○ glycolysis, pyruvate oxidation, citric acid cycle, electron transport chain.

Explanation:

To determine the correct order of aerobic cellular respiration stages, we recall the process:

1. Glycolysis: Breaks down glucose into pyruvate in the cytoplasm.
2. Pyruvate Oxidation: Converts pyruvate to acetyl - CoA in the mitochondrial matrix.
3. Citric Acid Cycle (Krebs Cycle): Uses acetyl - CoA to produce energy - carrying molecules (NADH, FADH₂) in the mitochondrial matrix.
4. Electron Transport Chain: Uses NADH and FADH₂ to generate ATP, occurring in the inner mitochondrial membrane.

Now we analyze the options:

• The first option has the wrong order as glycolysis should come first, not the citric acid cycle.
• The second option incorrectly places the citric acid cycle before pyruvate oxidation.
• The third option also has the wrong order of citric acid cycle and pyruvate oxidation.
• The fourth option (glycolysis, pyruvate oxidation, citric acid cycle, electron transport chain) follows the correct sequence of aerobic cellular respiration.

Answer:

D. glycolysis, pyruvate oxidation, citric acid cycle, electron transport chain.