The process which removes/eliminates
excretory wastes to the outside of the
organism.
This is necessary, because:
- accumulation of metabolic waste would slow down and evenutally stop chemical reactions which makes up an organism's metabolism and to maintain its equilibrium.
- excretory waste are toxic, interfering with key metabolic steps.
- diluting effect of the excessive accumulation of water within a cell also slows down metabolic reactions.