why aquatic animals are affored to be ammonotelic
Ammonotelism is the type of excretion in which ammonia is the main nitrogenous waste material. Such animals are called ammonotetic.
It is found in aquatic animal groups like sponges, coelentrates, crustaceans, echinoderms, bony fish, tadpole larvae and salamander.
Ammonia is highly toxic and must be metabolised or expelled from the body as soon as possible.
Ammonia is highly soluble in water and a very large volume of water is needed by the animal to dissolve ammonia. 1 gm of ammonia needs about 300 - 500 ml of water. But this is not a problem for animals living in an aqueous habitat which are generally found to be ammonotelic.