5.2.2

Anaerobic Respiration

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Anaerobic Respiration

The end product of glycolysis is pyruvate and this can then be used in aerobic or anaerobic respiration. There are two types of anaerobic respiration: ethanol fermentation and lactate fermentation.

Illustrative background for Ethanol fermentationIllustrative background for Ethanol fermentation ?? "content

Ethanol fermentation

  • Ethanol fermentation is the conversion of pyruvate to ethanol under anaerobic conditions.
  • This process only takes place in plants and yeast.
Illustrative background for Pyruvate → ethanolIllustrative background for Pyruvate → ethanol ?? "content

Pyruvate → ethanol

  • Pyruvate is first converted to ethanal by the enzyme pyruvate decarboxylase.
    • CO2 is produced as a by-product.
  • Ethanal is then reduced to ethanol.
    • This reaction is catalysed by ethanol dehydrogenase.
    • NADH is oxidised to NAD.
Illustrative background for Lactate fermentationIllustrative background for Lactate fermentation ?? "content

Lactate fermentation

  • Lactate fermentation is the conversion of pyruvate to lactate.
  • This process takes place in animals and some bacteria. It is common in skeletal muscle when there is an insufficient oxygen supply, such as during exercise.
Illustrative background for Pyruvate → lactateIllustrative background for Pyruvate → lactate ?? "content

Pyruvate → lactate

  • Pyruvate is reduced to lactate.
    • This reaction is catalysed by lactate dehydrogenase.
    • NADH is oxidised to NAD.

Jump to other topics

1Biological Molecules

2Cells

3Substance Exchange

4Genetic Information & Variation

5Energy Transfers (A2 only)

6Responding to Change (A2 only)

7Genetics & Ecosystems (A2 only)

8The Control of Gene Expression (A2 only)

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