Why is it necessary to excrete waste products?

Unicellular living forms release waste from their cell surfaces. Complex creatures like humans excrete waste through urine and feces. All life forms excrete in some manner. All living organisms are made of cells, and metabolic events take place inside them. Metabolism releases wastes such as water, CO₂, urea, uric acid, etc. These elements are poisons the body shouldn't accumulate. Excretory organs dispose of metabolic waste.

If these gases or wastes were not permitted to escape the body, they would clog other parts, reducing its overall efficiency or perhaps causing a breakdown. Humans and other creatures must also consume energy-containing molecules like food, water, and oxygen. Excretion removes waste from the body before it accumulates and disrupts normal function.

Blocking an organism's waste disposal mechanism would be as devastating as cutting off its food, air, and water. The metabolic process also creates toxic poisons that must be eliminated from the body immediately. Excretory functions must act continually so that other chemical processes can work.

Cellular processes produce metabolic waste.

Non-metabolic waste includes materials that the body cannot utilize and passes through the digestive tract.

Hence, it is necessary to remove such poisonous waste materials from our bodies through the excretory system.