Question

Write the classification of animals on the basis of excretory substance.

Answer 1

Based upon the type of nitrogeneous waste excreted, the animals are classified into the following categories:

(i) Ammonotelic Organisms:

Ammonotelic organisms are those which excrete nitrogenous waste in the form of ammonia.

e.g., octopus, sepia and bony fishes, pila, earthworm, amoeba, leech etc.

(ii) Ureotelic Organisms:

Uteotelic organisms are those which excrete nitrogenous waste in the form of urea.

e.g., mammals, amphibians, aquatic and semi-aquatic reptiles etc.

(iii) Uricotelic organisms:

Uricotelic organisms are the organisms which excrete nitrogenous waste in the form of uric acid.

e.g., Lizard, some insects and birds etc.