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  1. Glossary
  2. /Biology
  3. /Cellular Respiration

What is Cellular Respiration?

In short

Cellular respiration is the process in which cells break down glucose to release energy, stored as ATP. It is not the same as breathing.

In simple words

In aerobic respiration, glucose reacts with oxygen: C6H12O6+6 O2→6 CO2+6 H2O+energy\text{C}_6\text{H}_{12}\text{O}_6 + 6\,\text{O}_2 \rightarrow 6\,\text{CO}_2 + 6\,\text{H}_2\text{O} + \text{energy}C6​H12​O6​+6O2​→6CO2​+6H2​O+energy. It begins in the cytoplasm with glycolysis and finishes in the mitochondria. Anaerobic respiration happens without oxygen: it makes ethanol and carbon dioxide in yeast and lactic acid in muscles. It gives much less energy.

Example

One molecule of glucose gives about 303030 to 323232 molecules of ATP in aerobic respiration, and only 222 in anaerobic respiration.

Also searched as: respiration takes place in, respiration experiment.

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  • Lessons on this topic
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Related terms

  • Photosynthesis
  • Parts of a Cell (Organelles)
  • Enzyme

← All glossary terms

Learn it in

  1. Respiration: Releasing Energy from FoodClass 9 to 10
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Practise

  1. An oxygen molecule would take about three years to diffuse from your lungs to your toes…Medium
  2. Take a simple model: the two lungs hold 300 million alveoli, and each one is a tiny ball…Hard
  3. At rest, Dev takes 16 breaths a minute, with 0.5 L of air in each…Medium
  4. Put these in the order in which air passes them: bronchi, nostrils, alveoli, trachea…
Easy
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Quick questions

  1. Insects have no lungs. How does oxygen reach the cells in an insect's legs?Medium
  2. Haemoglobin has a high affinity for oxygen. A person has far fewer red blood cells than…Hard
  3. A model lung has 5 × 10⁸ alveoli, each with a surface of 0.12 mm². What is their total…Hard

More Biology terms

  1. Algae
  2. Bacteria
  3. Binomial Nomenclature
  4. Cell
  5. Diffusion and Osmosis
  6. DNA
All Biology terms →

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