Question

How would you explain the role of oxygen in aerobic respiration?

Answer 1

O2 is the final electron acceptor (from outside the cell, so it's an exogenous acceptor).

Explanation:

Remember that aerobic respiration is a three-stage process for glucose...

1. Glycolysis: Initial oxidation and degradation of glucose to pyruvate (produces some ATP, as well as NADH, FADH2, or both)

2. Tricarboxylic acid cycle (TCA cycle) or Krebs or Citric acid cycle: Oxidation and degradation of pyruvate
   to CO2 (produces some ATP or GTP, as well as NADH, and FADH2)

3. ETC: NADH and FADH2 formed by glycolysis and TCA cycle are oxidized by an ETC, using O2 as the terminal electron acceptor (produces LOTS of ATP)