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- Aerobic and anaerobic respiration
Aerobic and anaerobic respiration
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Respiration releases energy from glucose in every living cell. It is not the same as breathing.
Aerobic respiration
glucose + oxygen → carbon dioxide + water
Happens in mitochondria. Releases a lot of energy. It is exothermic.
Happens in mitochondria. Releases a lot of energy. It is exothermic.
Anaerobic respiration
In muscles: glucose → lactic acid. Releases less energy. Lactic acid builds up and causes an oxygen debt, repaid by deep breathing afterwards.
In plants and yeast: glucose → ethanol + carbon dioxide (fermentation), used in bread and brewing.
In plants and yeast: glucose → ethanol + carbon dioxide (fermentation), used in bread and brewing.
Comparison
Why do you keep breathing heavily after a sprint?
- Anaerobic respiration produced lactic acid.
- Extra oxygen is needed to break it down.
- This is repaying the oxygen debt.
Answer: To repay the oxygen debt.
Aerobic: glucose + oxygen → carbon dioxide + water, lots of energy, in mitochondria. Anaerobic: glucose → lactic acid in muscles, or ethanol + carbon dioxide in yeast, less energy.
The interactive lesson includes the diagrams for this topic.
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