AP Biology / Unit 3: Cellular Energetics
3.5 Cellular Respiration
Notes
- Glycolysis (cytoplasm): glucose → 2 pyruvate, small ATP yield.
- Pyruvate oxidation and Krebs cycle (mitochondrial matrix): release $\mathrm{CO_2}$, make NADH and FADH₂.
- Electron transport chain (inner membrane): $\mathrm{O_2}$ is the final electron acceptor; $\mathrm{H^+}$ gradient drives ATP synthase (most ATP).
- Fermentation regenerates NAD⁺ without oxygen.
Practice
The final electron acceptor in aerobic respiration:
Oxygen becomes water.
Most ATP from respiration is made:
Chemiosmosis yields the most.
Fermentation's main job is to:
Without NAD⁺, glycolysis stops.
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