They are typically composed of thousands of atoms or more. The most common macromolecules in biochemistry are biopolymers nucleic acids, proteins, carbohydrates and lipids and large non-polymeric molecules such as lipids and macrocycles
A population that has been isolated, especially a smaller one, could have a high level of homozygosity and therefore not a lot of genetic variation. Gene flow between such populations can increase the level of heterozygosity, and therefore up genetic variation.
1, O because if either shows present it's O.
