Theme 1 - DNA and Evolution (1.2-1.5)

genome

a person’s unique genetic code

nucleotide

smallest unit of DNA, has a phosphate, sugar, and base (A, T, C, or G)

mutation

a mistake in a DNA base pair copied from another cell
can be inherited by children if occurs in sex cells

genetic recombination

exchange and rearrangement of genetic material between sexual partners

gene flow

influx of genetic traits from outside populations

analogous structure

similar-looking trait in two species that developed separately from each other

homologous structure

trait in two species developed from common ancestor and adjusted to each one’s environment

convergent evolution

two species independently evolve to have similar traits

divergent evolution

two species with common ancestor branch out to develop different traits

macroevolution

large trait differences that create new species

microevolution

small changes in the frequency of traits within a species across generations

gene pool

collection of genes within a population

modern synthesis

theory connecting evolutionary pressures to changes in a species’ genetic makeup

genetic drift

decrease in trait variation in a species due to random events

bottleneck effect

type of genetic drift caused by natural disaster

founder effect

type of genetic drift caused by migration of unique group within species into a new population