Why does respiration release energy

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.

Respiration must happen all of the time so that the organism can survive. Respiration releases energy - it is an exothermic process. The energy is stored in molecules of ATP.

ATP can be broken down in other processes in cells to release the stored energy. Here is the word equation for anaerobic respiration in humans:. Anaerobic respiration produces much less energy than aerobic respiration.

The waste product, lactic acid , builds up in the muscles causing pain and tiredness. This leads to cramp. Lactic acid is only broken down when you start aerobic respiration again. Anaerobic respiration happens in microorganisms such as bacteria because they need to release energy from glucose too. Yeast, which are unicellular fungi, can carry out an anaerobic process called fermentation. Here is the word equation for fermentation:. The ethanol alcohol is useful for brewers and wine-makers, and the carbon dioxide is useful to bakers because it helps their bread rise.

The table compares the main features of aerobic and anaerobic respiration:. Build your knowledge with top universities and organisations. Learn more about how FutureLearn is transforming access to education.

Learn more about this course. Energy released from respiration Metabolic pathways provide resources and energy that allow cells to grow and divide. Share this post. Metabolic pathways provide essential resources and energy that all cells need to be able to grow and divide. The amount of energy obtained from these pathways can vary depending upon the environment and conditions of the cell, as can be seen by the examples included below. Want to keep learning? See other articles from this course.

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