During puberty, teenagers will encounter body odour problem.
Explain how this problem occurs.​

Animal bodies (and even plant bodies for that matter) are complex enough that life couldn't exist without enzymes. enzymes are usually large, complex biological catalysts that are expensive to make. enzymes speed up the rate of chemical reactions without being used up during the reaction (they can be reused many times). they are highly specific in the reactions they regulate. knowing what enzymes are and how they function, why does this explain why complex life forms could not exist if there were no enzymes.

What must be true for natural selection to heppen

What was the land like over 500 million years ago? what was under the sea?