Answer:
Excretion
Explanation:
The excretory system removes cellular wastes and helps maintain the salt-water balance in an organism. When cells break down proteins, they produce nitrogenous wastes, like urea. The excretory system serves to remove these nitrogenous waste products, as well as excess salts and water, from the body.
Answer:
Natural selection occurs when some of those traits help some individuals survive and reproduce more than others. That causes their genes to become more common in the population over time, and it's the way species evolve to adapt to changes in their environment.
Explanation:
hope this helps =)
