_In the metabolism surso the animals produce waste that is necessary to eliminate, because they are often toxic, among the lower organisms the protozoa the elimination of these products do not pose special problems and is carried out through vacuoles that accumulate them first and then pour them directly to the outside, among the metazoans the elimination of waste requires special devices to expel gaseous substances such as carbonic anhydride, the respiratory system is used, and for solids or liquids there are structures often linked to the digestive system, the excess of salts or water is also eliminated through various glands, for example, the sweat in humans but the final product of the disintegration of proteins, ammonia, often poses problems to terrestrial organisms, most of the aquatic animals eliminate it directly in the water, but terrestrial species have to transform it into uric acid or urea that are toxic, insects reptiles and birds produce uric acid in the form of crystals while mammals synthesize urea and eliminate it in liquid form ....
Authors get paid when people like you upvote their post.
If you enjoyed what you read here, create your account today and start earning FREE STEEM!
If you enjoyed what you read here, create your account today and start earning FREE STEEM!