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Respiration - AQAAnaerobic respiration

All organisms respire in order to release energy to fuel their living processes. The respiration can be aerobic, which uses glucose and oxygen, or anaerobic which uses only glucose.

Part of Combined ScienceBioenergetics

Anaerobic respiration

Anaerobic respiration in yeast

Anaerobic respiration is economically important 鈥 many of our foods are produced by microorganisms respiring anaerobically.

A ball of dough covered in flour

Yeast is used to make alcoholic drinks. When yeast cells are reproducing rapidly during beer or wine production, the oxygen runs out. The yeast switches to anaerobic respiration. Ethanol and carbon dioxide are produced.

Yeast can also be used to produce bread. Yeast respires using sugar added to the dough. Bubbles of carbon dioxide make the bread rise. The alcohol that鈥檚 produced as the bread is baked.

Anaerobic respiration in plants

Certain plants, and plant cells also respire anaerobically. These include plants that grow in marshes, where oxygen concentrations will be low.

A bog which is flooded with water