Protein compound which brings about changes in other organic compounds without being changed or broken down itself

Enzymes

Enzymes are biological substances that catalyse chemical reactions and they regulate the rate at which chemical reactions peoceed without itself being altered in the process. However, enzymes act on the molecules called substrate and thereby convert them different molecules known as products.

answer; i believe the answer is (polygenic inheritance;

clumped distribution, because you'de have all of the population gathered in a relatively small are.

it's the most common because it provides protection and a mate for reproduction

example: humans, seeweed, cattles, etc.