Class 11 Biology Chapter 12 Respiration in Plants – Revision Notes

Quick revision notes for Class 11 Biology Chapter 12 (Respiration in Plants). These Class 11 Biology Chapter 12 notes are ideal for quick revision just before exams.

Glycolysis

• Cytoplasm; glucose → 2 pyruvate; net 2 ATP, 2 NADH.

Fermentation

• Alcoholic (yeast: ethanol+CO₂) or lactic acid; net 2 ATP; incomplete oxidation.

Aerobic Respiration

• Krebs cycle (mitochondrial matrix): Acetyl CoA → CO₂+NADH+FADH₂+ATP.
• ETS (inner mitochondrial membrane): oxidative phosphorylation, O₂ final acceptor, ~36-38 ATP total.

RQ

• RQ=CO₂ evolved/O₂ consumed; =1 (carbs), <1 (fats/proteins), >1 (organic acids).

One-Line Summary

Cellular respiration breaks down glucose via glycolysis, and either fermentation (anaerobic, low ATP yield) or the Krebs cycle plus electron transport chain (aerobic, high ATP yield via oxidative phosphorylation with oxygen as final electron acceptor).

Written by Satish

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