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Waveform Audio File Format  |  1995-06-29  |  395.5 KB  |  1 channel  |  22,050 sample rate  |  36 seconds  |  [TEXT/LMAN]
Transcription: The chemical reactions that take place inside cells produce waste products. Getting rid of these is called excretion. Excretion is necessary because if the waste products were allowed to build up, they would poison and kill the organism. Plants and animals excrete carbon dioxide from respiration. Plants also excrete oxygen, a waste product of photosynthesis during the day. Animals need to get rid of waste from the breakdown excess proteins in their diet. Expelling waste matter after digestion is egestion, not excretion.