What you'll learn
How organisms release energy.
Key ideas
- Aerobic and anaerobic respiration (lactic acid in humans, ethanol + CO₂ in yeast).
- Gas exchange and breathing.
Exam tips
- Learn the word equations.
- Test for CO₂ with limewater.
Common mistakes
- Confusing respiration with breathing.
- Muddling human and yeast anaerobic products.