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26 terms


change over time; process by which modern organisms descended from ancient organisms
well-tested, well-supported explanation that unifies a broad range of observations
preserved remains of an ancient organism
natural variation
differences among individuals of a species; results from mutation and sexual reproduction
struggle for existence
competition between organisms for food and space
ability of an organism to survive and reproduce in its environment
inherited characteristic that increases an organism's chance of survival
survival of the fittest
individuals that are better suited to their environment survive and reproduce most successfully; natural selection
natural selection
individuals that are better suited to their environment survive and reproduce most successfully; survival of the fittest
homologous structure
structures that have different mature forms but develop from the same embryonic tissues
vestigial structure
organ so reduced in size, it does not serve an important function; may be homologous to structures in other organisms
two organisms that are so similar they can interbreed in nature and produce fertile offspring
formation of a new species as a result of reproductive isolation
reproductive isolation
separation of species that prevents them from interbreeding and producing fertile offspring
behavioral isolation
type of reproductive isolation in which two organisms have different mating rituals that prevent them from interbreeding
geographic isolation
type of reproductive isolation in which two populations are separated by geographic barries like mountains or bodies of water
variety of organisms that exist in the biosphere
classification of organisms
binomial nomenclature
two part scientfic name for an organism; its genus is listed first, followed by its species
first part of an organism's scientific name
second largest taxonomic group; there are six - animalia, plantae, protista, eubacteria, archaebacteria, fungi
most inclusive taxonomic group, larger than kingdom; three exist - bacteria, archaea, eukaryota
a single celled plant or animal, ex. amoeba, paramecia, euglena
divergent evolution
pattern of evolution in which two species become more and more dissimilar
kingdom of heterotrophs that obtain nutrients through absorption, ex. mushrooms, yeasts
domain of organisms that contain nuclei, includes animals, plants, fungi, and protists