Why do you need excretion in the first place?
Your cells are constantly making waste as they do their jobs,kind of like how your phone fills up with junk files the more you use it. If you didn't get rid of these waste products, they'd build up and poison your body from the inside out.
Excretion is how your body removes these toxic leftovers. Without it, your organs would get overwhelmed by things like carbon dioxide and urea.
Excretion is the process where your body gets rid of harmful waste products made during chemical reactions inside your cells.
This is different from egestion, which is just pushing out undigested food (like what happens when you poop). Excretion deals with wastes produced inside your body, not leftover food from your diet.
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