IGCSE Biology glossary
Anaerobic
Biology editorial review is supported by the named review panel. Reviewer participation may vary by guide. Checked against Cambridge IGCSE Biology 0610 (2026–2028); last reviewed August 2026.
Definition
A process that occurs without oxygen. In anaerobic respiration, glucose is only partially broken down, releasing less energy than aerobic respiration. In animals, glucose produces lactic acid. In yeast, glucose produces ethanol and carbon dioxide (fermentation).
What to include in an exam answer
Anaerobic respiration releases LESS energy because glucose is not fully broken down. Know the two different equations: in animals (glucose produces lactic acid) and in yeast (glucose produces ethanol + carbon dioxide). These differ.
Example in context
Write the word equation for anaerobic respiration in yeast: glucose produces ethanol + carbon dioxide (plus a small amount of energy released).
Related syllabus topic
Respiration