What is the best descripition of a chromosome

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.

3test questions with answers on incomplete dominance

Why does competiton happen? a: different organisms have different needsb: there are limited resources in an ecosystemc: there are no predators in an ecosystemd: organisms do not need the same resources (i think it's b but i'm not sure)