Which term best describes the set of genetic material contained within a population, representing its total genetic diversity?

• A. Gene pool
• B. Carrying capacity
• C. Pioneer species
• D. Population density

Answer: (A)

Think of the genetic material in a population as a shared library of alleles. The term that describes the entire collection of those alleles and their frequencies is the gene pool. It represents the population’s total genetic diversity and is the source of variation on which evolution acts. Over time, the gene pool can shift as new mutations arise, individuals migrate, random genetic drift occurs, or natural selection changes allele frequencies. The other terms describe something different: carrying capacity is how many individuals the environment can support; pioneer species are the first organisms to colonize a new habitat; population density is how many individuals live in a given area. So the gene pool is the best fit for the set of genetic material within a population.