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Anaerobic respiration

 

The gas exchange system


Respiration is a process that breaks down glucose to release energy in every cell of the human body and all living things. Respiration is different from breathing, which is scientifically called ‘ventilation’.

 

Respiration needs glucose, which comes from food. Without respiration, cells would die. There are two kinds of respiration:

 

Respiration that uses oxygen is called aerobic respiration. It happens in most cells most of the time.


Respiration that does not use oxygen is called anaerobic respiration. It happens less often than aerobic respiration.


Humans do both types of respiration. They do aerobic respiration when they have enough oxygen. They switch to anaerobic respiration when they are short of oxygen.

Respiration happens in mitochondria, which are tiny parts of the cells in the cytoplasm. Cells that need more energy, such as sperm cells or muscle cells, have more mitochondria.

 

Some organisms, like bacteria and yeast, do a different kind of anaerobic respiration called fermentation.

 

Anaerobic respiration in humans


When you exercise hard, your body cells may not have enough oxygen for respiration to take place and anaerobic respiration occurs instead.

The formula for this is:

 

glucose → lactic acid

 

Anaerobic respiration releases less energy than aerobic respiration, but does this more quickly. The result of this reaction is lactic acid. This builds up in muscles causing pain and tiredness, which can lead to cramp.

 

After you exercise hard, you keep breathing fast and deep for a while. This is called excess post-exercise oxygen consumption or EPOC. It used to be called ‘oxygen debt.’ During this time, oxygen reacts with lactic acid to make carbon dioxide and water, and release the rest of the energy from glucose.

 

Summary:

 

  • Respiration is a process that breaks down glucose to release energy in every living cell.
  • Respiration that does not use oxygen is called anaerobic respiration. It produces less energy than respiration that uses oxygen, but it does it faster.
  • Fermentation is a type of anaerobic respiration that happens in microorganisms.

 

 

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