The process of removal of waste products from the body is known as excretion.
Excretion is generally observed in every living organism, so, it is an important life process.
Excretory products are generally created as a by-product of metabolic & non-metabolic activities.
The waste products animals generate are then classified as either metabolic wastes or non-metabolic wastes.
Metabolic wastes are also generated as a by-product of metabolic activities. Eg. of metabolic wastes which includes gases, liquids and solids. Non-metabolic wastes are normally generated when a substance is no longer usable or digestible by an organism.
In humans, the excretory system includes the following organs: