Aerobic respiration

Respiration using oxygen to break down food molecules is called aerobic respiration. Glucose is the molecule normally used for respiration – it is the main respiratory substrate. Glucose is oxidised to release its energy.

The word equation for aerobic respiration is:

glucose + oxygen → carbon dioxide + water + energy released

The reactants in this reaction are glucose and oxygen. The products are carbon dioxide and water.

Symbol equation - Higher

You need to be able to recognise the chemical symbols:

C6H12O6 + 6O2 → 6CO2 + 6H2O

Respiration is a series of reactions, but this summarises the overall process.

The first stages of respiration occur in the cytoplasm of cells, but most of the energy released is in the mitochondria.