lesson
Without oxygen, the products can differ
1 · Learn
Anaerobic processes transfer energy without using oxygen in the reaction. In human muscle cells, anaerobic breakdown of glucose produces lactate, often called lactic acid in school word summaries. In yeast, fermentation produces ethanol and carbon dioxide.
These processes transfer less energy per glucose molecule than aerobic respiration. Do not use one organism's products as the automatic answer for every organism, or confuse anaerobic respiration with breathing out.
2 · Worked example
I explain that bubbles from a supplied yeast-fermentation observation are consistent with carbon dioxide production, not proof that human muscles produce ethanol.
3 · Your turn
Which products belong to yeast fermentation in this model?
Check your answer
Ethanol and carbon dioxide.
4 · Apply your learning
Compare supplied process cards for muscle and yeast, identifying inputs, products and limits without conducting a fermentation experiment.
Adult guidance and safety
Use supplied evidence and approved diagrams. Practical work requires a qualified adult, suitable equipment and a risk assessment. No unsupervised chemicals, heating, flames, mains electricity or bright-light experiments. Human biology is factual education, not personalised medical advice; never request intimate or health disclosures.
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