simplified

• Explain how the conversion of pyruvate to lactate allows ATP to be continuously produced.

  In anaerobic respiration in animals, pyruvate is reduced to lactate as it gains hydrogens from NADH. Therefore, NADH is oxidised into NAD. The NAD formed in this reaction returns back to glycolysis, ensuring glycolysis can continue and ATP can be produced.
• Explain why more ATP is produced in aerobic respiration compared to anaerobic respiration.

  From a single molecule of glucose, there’s an overall yield of 2 ATP in anaerobic respiration. This is because the only stage that produces ATP is glycolysis. However, in aerobic respiration, ATP is made in glycolysis, the Krebs cycle and oxidative phosphorylation. From a single glucose molecule, it’s possible for over 30 ATP molecules to be made during oxidative phosphorylation. Therefore, aerobic respiration produces more ATP than anaerobic respiration.
• In plants, for a single molecule of glucose, how many CO2​ molecules are produced in aerobic respiration?

  6
• In plants, for a single molecule of glucose, how many CO2​ molecules are produced in anaerobic respiration?


  2