Pearson Edexcel International GCSE Biology · specification 4BI1 · Paper 2 | Whole paper: All content including bold B statements · Free · no account needed
2(f) Respiration (4BI1 specification)
How every cell releases energy, with and without oxygen, and why the two routes give such different yields.
Learn it on Incandio
The 3 Incandio pages that teach this — each explained in full, then proved in marked questions, taught back to an AI pupil and defended in a debate. Completely free.
- Respiration and ATP — What respiration is actually for, why every living cell does it every second, and why breathing is not the same thing at all.
- Anaerobic Respiration — The backup that runs without oxygen — why it is worth having, why it cannot last, and why bread and beer both depend on it.
- Gas Exchange in Plants, Day and Night — Two opposite processes in one leaf, one of which never stops — and why what you can measure at the surface is only the difference between them.
The teaching route this belongs to: Topic 2 · Structures and functions in living organisms (Biology) — the lessons in order, with every gate.
Specification coverage
Topic 2 Structures and functions in living organisms (f) Respiration — statements 2.37–2.41B (includes bold B statements assessed on Paper 2 only)
Assessment objectives: AO1, AO2, AO3. Suggested learning time: 60 minutes.
Required knowledge
- Respiration as the release of energy from glucose in every living cell
- The word and balanced chemical equations for aerobic respiration
- The word equations for anaerobic respiration in muscle and in yeast
- The difference in energy yield between aerobic and anaerobic respiration
- Bold B statements: oxygen debt and the fate of lactic acid
Required skills
- Distinguish respiration from breathing in every answer
- Explain why anaerobic respiration is used despite its low yield
- Interpret data on oxygen uptake during and after exercise
- Describe and evaluate the required practical: Investigate the evolution of carbon dioxide and the uptake of oxygen by respiring organisms.
How it is examined
- Multiple-choice and short-answer recall
- Application of the content to an unfamiliar context
- Extended open-response, marked on the quality of a connected explanation
- Practical questions on method, variables, data and sources of error
Common mistakes
- Using 'respiration' to mean breathing. This single confusion loses marks throughout the paper.
- Saying respiration 'produces energy'. Energy is released from glucose, not created.
- Giving the yeast equation for muscle. Humans do not produce ethanol.
This page maps the specification. The pages above teach it, and the Biology lessons hold the whole course — completely free.