Question

Most fishes get rid of nitrogenous wastes by

A) converting it into urea and excreting through the skin
B) storing it in specialized cells for later elimination
C) eliminating ammonia from the gills and kidneys
D) releasing it through the digestive system

Answer 1

Fishes primarily excrete nitrogenous wastes by eliminating ammonia through their gills and kidneys, classifying them as ammonotelic.

Step-by-step explanation:

Most fishes excrete nitrogenous wastes by eliminating ammonia through their gills and kidneys. In the breakdown of nitrogen-containing macromolecules such as proteins and nucleic acids, excess nitrogen is excreted from the body. In aquatic environments, animals such as fishes easily release this toxic ammonia into the water, as they are ammonotelic organisms. Terrestrial organisms have adapted to converting ammonia into less toxic substances like urea or uric acid due to the difficulty of excreting ammonia on land. This evolutionary adaptation minimizes water loss and conserves energy, crucial for survival in different ecosystems.