Anaerobic respiration

• What is anaerobic respiration?

  Anaerobic respiration is a type of respiration that occurs without oxygen.
• Why is anaerobic respiration not the best way to transfer energy from glucose?

  Because it produces much less energy per glucose molecule, only 2 molecules of ATP.
• How many ATP molecules are produced during anaerobic respiration?

  2 molecules of ATP are produced.
• What do animals produce during anaerobic respiration?

  Animals produce lactic acid during anaerobic respiration.
• What happens to muscles during vigorous exercise when oxygen supply is insufficient?

  • Muscles start respiring anaerobically.
  • Glucose is only partially broken down.
  • Lactic acid is produced, leading to pain and fatigue.
• What is the word equation for anaerobic respiration in animals?

  glucose → lactic acid
• What is the effect of lactic acid buildup in muscles?

  It causes pain and muscle fatigue.
• What is meant by "oxygen debt" after anaerobic respiration?

  It refers to the extra oxygen needed to break down lactic acid and resume aerobic respiration.
• Under what conditions do plants resort to anaerobic respiration?

  In waterlogged soil where there is little or no oxygen.
• What do plants and fungi produce during anaerobic respiration?

  They produce ethanol and carbon dioxide.
• What is the word equation for anaerobic respiration in plants and fungi?

  glucose → ethanol + carbon dioxide
• What are the main differences between aerobic and anaerobic respiration?

  | | Aerobic | Anaerobic |

  | --------- | --------------------- | ---------------------------------------------- |

  | Conditions | Oxygen present | Not enough oxygen present |

  | Substrate | Glucose (or another organic molecule) | In animals - lactic acid |

  | Products | Carbon dioxide and water | In plants and some fungi - ethanol and carbon dioxide |

  | Energy transferred | Lots - 32 ATP made | Much less - 2 ATP made |
• What color does hydrogen-carbonate solution turn when CO₂ is present?

  It turns yellow when there’s plenty of CO₂ present.
• What is the procedure to detect carbon dioxide production during respiration using dried beans?

  1. Germinate dried beans for a day or two.
  2. Place healthy and dead beans in separate test tubes.
  3. Add hydrogen-carbonate indicator and gauze.
  4. Leave for a period of time to observe color change.
• How can you measure the energy transferred by heat during respiration?

  By using vacuum flasks with germinating beans and recording temperature changes.
• What should be done to ensure the beans can respire aerobically in the heat measurement experiment?

  Leave some air in the vacuum flask.
• Why is it important to comment on experiments?

  To check the independent variable and note any changes.
• What is the control tube in the CO₂ detection experiment with small organisms?

  The control tube is just the test tube without organisms.
• What should you avoid doing in the respiration experiments with germinating beans?

  You should avoid killing the germinating beans.