AP BIOLOGY

Detailed explanation-1: -Populations (or gene pools ) evolve as gene frequencies change; individual organisms cannot evolve. Variation in populations is determined by the genes present in the population’s gene pool, which may be directly altered by mutation.

Detailed explanation-2: -What is the best explanation for a population being described as an evolutionary unit? Explanation: The genetic make up of populations can be measured over time.

Detailed explanation-3: -Evolution is not measured in individuals because individuals cannot undergo evolution. Evolution does not refer to changes in an individual’s traits, but rather a change in the frequency of traits present in all organisms in the population.

Detailed explanation-4: -Individual organisms don’t evolve. Populations evolve. Because individuals in a population vary, some in the population are better able to survive and reproduce given a particular set of environmental conditions.

Detailed explanation-5: -All evolution means is that a population is changing in its genetic makeup over generations. And the changes may be subtle-for instance, in a wolf population, there might be a shift in the frequency of a gene variant for black rather than gray fur. Sometimes, this type of change is due to natural selection.