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IGCSEBiology
Trial Class

Original practice · 5 questions · 15 marks · about 17 minutes

Comparing Aerobic and Anaerobic Respiration Practice Questions

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.

These questions bring together aerobic and anaerobic respiration, testing your ability to compare their features, advantages, and limitations.

Before you open the answers

  • Attempt every question without notes.
  • Show working for calculations and write complete biological statements.
  • Use the suggested time as a guide, not a strict limit on the first attempt.

These are original practice questions. They do not reproduce an official Cambridge paper or official mark scheme.

  1. Question 1

    Paper 4 Extended 4 marks Difficulty 3/5

    Draw a comparison table showing three differences between aerobic and anaerobic respiration.

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    1. Oxygen: aerobic requires O₂; anaerobic does not.
    2. Energy: aerobic releases more energy per glucose molecule; anaerobic releases less.
    3. Products: aerobic produces CO₂ and H₂O; anaerobic produces lactic acid (animals) or ethanol and CO₂ (yeast).
    4. Location: aerobic mainly in mitochondria; anaerobic in cytoplasm.

  2. Question 2

    Paper 4 Both 3 marks Difficulty 3/5

    Explain why organisms need both aerobic and anaerobic respiration.

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    1. Aerobic respiration is the main energy source: releases more energy per glucose.
    2. Anaerobic respiration provides energy when oxygen supply is insufficient (e.g. Intense exercise).
    3. Anaerobic respiration is a temporary solution: lactic acid must be broken down later.

  3. Question 3

    Paper 4 Extended 3 marks Difficulty 4/5

    Explain why anaerobic respiration in yeast produces different products from anaerobic respiration in humans.

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    1. Yeast has different enzymes to human muscle cells.
    2. In yeast, glucose is broken down to ethanol and carbon dioxide.
    3. In humans, glucose is broken down to lactic acid: different metabolic pathways are used.

  4. Question 4

    Paper 2 Core 2 marks Difficulty 2/5

    State the product of anaerobic respiration in humans that causes muscle fatigue.

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    1. Lactic acid.
    2. It builds up in muscles during intense exercise and causes cramp / pain.

  5. Question 5

    Paper 4 Extended 3 marks Difficulty 4/5

    A student investigates respiration in germinating seeds using a respirometer. Explain why the seeds are placed on moist cotton wool and kept at a constant temperature.

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    1. Moist cotton wool provides water for the seeds to germinate / for metabolic reactions.
    2. Constant temperature ensures any changes in gas volume are due to respiration, not temperature changes.
    3. Temperature affects the rate of enzyme-controlled reactions: controlling it makes the experiment a fair test.

Mark the set consistently

Award a point only when the idea is clearly present in the written answer. Correct any missed point in a complete sentence, then test the same skill on a different question several days later.

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