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Cellular respiration

Review your understanding of cellular respiration in this free article aligned to NGSS standards.

Key points:

  • Cellular respiration is a process that happens inside an organism’s cells. This process releases energy that can be used by the organism to live and grow.
  • Many food molecules are broken down into glucose, a simple sugar. Glucose is used in cellular respiration.
  • Glucose and oxygen are inputs of cellular respiration. Carbon dioxide and water are outputs. This can be seen in the overall equation for cellular respiration:
  • In multicellular organisms, the steps of cellular respiration occur in the cytosol and the mitochondria.
A diagram represents the process of cellular respiration. A mitochondrion is shown in the center of the diagram. Arrows labeled glucose and oxygen point from the surrounding area to the mitochondrion. Arrows labeled carbon dioxide and water point from the mitochondrion to the surrounding area. The diagram indicates that energy is an output of cellular respiration.
Cellular respiration provides energy that an organism can use to live and grow. Image created with Biorender.com.

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