respiration

• name 2 molecules needed for aerobic respiration that can move into the mitochondria(2)

  pyruvate or NADH produced in glycolysis
• explain the increase in blood lactate concentration observed at the start of exercise(2)

  • muscle cells release lactate into blood due to anaerobic respiration
  • as there is insufficient oxygen for aerobic respiration
• explain why some ATP is broken down during glycolysis

  • to provide phosphates for phosphorylation of glucose
  • hydrolysis of ATP provides energy to break bonds in glucose
  • producing 2 triose phosphates
• deduce what happens to lactate in liver cells(2)

  • lactate is oxidisedd and converted to pyruvate
  • pyruvate is converted to glucose or glycogen
  • glucose or pyruvate used in respiration
• explain the need for reduced NAD to be oxidised in a mitochondrion(2)

  • release hydrogen atoms so hydrogen can be delivered to ETC
  • to allow ATP synthesis/chemiosmosis