Biogeographic isolation refers to the separation of the members of the similar species, or a group of organisms, which breed and generate offspring that can further give rise to young ones.
The separation can be achieved by the geographical forces like oceans, rivers, and mountains, and by the biological forces, like hunting times, and spring or fall mating.
Crossing over, or recombination, is the exchange of chromosome segments between nonsister chromatids in meiosis. Crossing over creates new combinations of genes in the gametes that are not found in either parent, contributing to genetic diversity.
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B. ATP synthase. The purpose of the hydrogen gradient is to take advantage of molecules' tendency to move from areas of higher concentration to areas of lower concentration. ATP synthase lets hydrogen ions flow through it to the matrix, and the energy from this flow is used by ATP synthase to synthesize ATP.
