5.5

• anaerobic respiration is the partial breakdown of hexose sugars (glucose) in oxygen-deprived conditions to produce a limited ATP yield
• The lactate produced in anaerobic respiration is transported to the liver in the bloodstream where it‘s oxidised to pyruvate by lactate dehydrogenase. This involves conversion of NAD to reduced NAD
• Lactate affect muscle contraction in mammals as it is acidic, so decreases the pH which results in muscle fatigue
• The ATP yield per molecule of hexose sugars in anaerobic respiration is 2 from glycolysis compared aerobic which in ideal conditions yield 38 ATP
• How could a student calculate the rate of respiration using a respirometer?

  • Volume of O2 produced or CO2 consumed / time x mass of sample
  • Volume = distance moved by coloured drop x (0.5 x capillary tube diameter)2 x π