Excretion in Animals

Excretion is concerned along with the removal of metabolic wastes that arise as a result of oxidation of energy rich compounds and metabolism of proteins and nucleic acids. This is performed in non-chordate metazoan animals through two distinct sets of tubular structures - the nephridia and coelomoducts. The nephridia and coelomoducts are variously named in different groups of animals depending upon their complexity and location. Terrestrial arthropods have evolved another kind of excretory organ known as Malpighian tubules structurally different form nephridia and coelomoducts.