Question

Difference between excretion vin animals and in humans

Answer 1

In animals excretion occurs through the process of diffusion while as humans have a well developed excretory system.

Answer 2

excretion in humans
  in humans  the removal of nitrogenous wastes from the body is called excretion or the elimination of wasteful metabolites, mainly of the nitrogenous nature is called as excretion.

excretion in plants 
 in plants, oxygen could be a waste product of as a result of photosynthesis; carbon dioxide a waste product of respiration and water as the waste product of both.

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