Define the different types of respiration.

Respiration is the process of transferring energy throughout cells within an organism. Energy is required for a lot of processes to take place in organisms such as: movement - for muscle contractions to take place, and homeostasis - to maintain processes such as body temperature in mammals and birds. Aerobic respiration uses oxygen to breakdown glucose to release energy: glucose + oxygen --> carbon dioxide + water ( + energy). Anaerobic respiration is used if there is not enough oxygen available and is the incomplete breakdown of glucose, so is a less efficient process of energy release than aerobic respiration. In muscle cells lactic acid is produced: glucose --> lactic acid ( + energy). In plants and yeast, ethanol and carbon dioxide are produced instead of lactic acid: glucose --> ethanol + carbon dioxide ( + energy).