Dear Student
Cellular respiration takes place in each and every living cell. Single celled organisms like Amoeba, Paramoecium etc. respire within their cell. Cellular respiration takes place in mitochondria and cytoplasm of the cell. Oxygen enters inside the cell through the cell membrane and burns the stored glucose to release energy inside the cell. Without energy the single celled organism cannot be able to perform other cellular functions. In the process of respiration the cell releases carbon dioxide which comes out.
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