In smaller organisms there are different ways of excretion of waste materials.
This depends on the arrangement of the body of the organism.
are let out directly
from the body. Nitrogenous wastes like ammonia and water are removed by the
- In multicellular organism like fishes or birds, nitrogenous wastes are of different types :
- In Earthworms , tubular structures called nephridia are the excretory organs. It’s moist skin also expels CO 2
- Fishes have ammonia as their waste product
- Birds excrete waste in the form of uric acid
- Human beings have urea as their nitrogenous waste