Aerobic respiration happens in four stages in order: glycolysis (G), link reaction (LR), Krebs cycle (KC) and oxidative phosphorylation (OP). Complete Table 3.1 to indicate which events occur in each stage of aerobic respiration. Use a tick (✓) to show that the event does happen, or a cross (✗) to show that it does not happen.
A new handheld technological device indicates the main type of respiratory substrate being used in a person's cells. The device includes a carbon dioxide sensor and an air-flow meter. The person breathes in through the device for a set time and then breathes out into it. The device works out the respiratory quotient (RQ) value to show whether the cells are mainly respiring carbohydrates or lipids. Explain how the device calculates the RQ value and how this shows whether the cells are mainly respiring carbohydrates or lipids.
State how the energy values of carbohydrates and lipids compare as respiratory substrates, and explain why there is a difference.