This set includes all of the vocabulary words for Chapters 10, 12, and 13 to help you prepare for Exam 3.

adaptive radiation

when a small number of species diversifies into a much larger number of species

allopatric speciation

speciation with geographic isolation

analogous trait

features that are produced by convergent evolution and are not inherited from a shared ancestor


a group of prokaryotes that are evolutionarily distinct from bacteria and thrive in some of the most extreme environments on Earth

background extinction

occurs at a lower rate during times other than periods of mass extinctions


the variety and variability among all genes, species, and ecosystems on Earth

biological species concept

species are populations of organisms that interbreed, or could possibly interbreed, with each other under natural conditions, and that cannot interbreed with organisms outside their own group


a classification of organisms consisting of related orders

convergent evolution

populations of organisms living in similar environments experience similar selective forces


the highest level of the hierarchy, including the bacteria, archaea, eukarya


the complete loss of all individuals in a species population


a classification of organisms consisting of related genera


a classification of organisms consisting of closely related species

homologous feature

traits that are inherited from a common ancestor


offspring of individuals of two different species


the interbreeding of closely related species


one of six categories into which all organisms on Earth are placed


a physical state characterized by the ability to replicate and the presence of metabolic activity


the accumulated effect of microevolution over a long period of time

mass extinction

a large number of species become extinct over a short period of time due to extraordinary and sudden environmental change


microscopic organism


a slight change in allele frequencies over one or a few generations


a membrane-enclosed, small, spherical unit containing a self-replicating molecule and carrying information, although no genetic material


all of the individuals are more closely related to each other than to any individuals outside of that group

morphological species concept

characterizes species based on physical features such as body size and shape


the common-ancestor points at which species diverge


a classification of organisms consisting of related families


the evolutionary history of organisms


a classification of organisms consisting of related classes


error during cell division in plants resulting in a doubling of the number of sets of chromosomes

postzygotic barrier

occur after fertilization and generally prevent the production of fertile offspring from individuals of two different species

prezygotic barrier

make it impossible for individuals to mate with each other, or if they can mate, make it impossible for the male's reproductive cell to fertilize the female's reproductive cell


includes most of the single-celled eukaryotes, such as algae

punctuated equilibrium

rapid periods of evolutionary change are punctuated by longer periods with little change

reproductive isolation

the inability of individuals from two populations to produce fertile offspring with each other

ring species

populations that can interbreed with neighboring populations but not with populations separated by larger geographical distances

RNA world hypothesis

the Earth may have been filled with RNA-based life before it became filled with the DNA-based life we see today


one species splits into two distinct species

speciation event

a point in evolutionary history at which a given population splits into independent evolutionary lineages


different kinds of organisms

specific epithet

a noun or adjective added to the genus name to distinguish a species

sympatric speciation

speciation without geographic isolation


classification process that names and arranges species in a manner that indicates the common ancestors they share and the points at which they diverged from each other


biological entities that can replicate but which can conduct metabolic activity only by taking over the metabolic processes of a host organism and therefore fall outside the definition of life


vascular, seed-producing flowering and fruit-bearing plants, in which the seeds are enclosed in an ovule within the ovary


the part of the male reproductive structure that produces pollen


three groups of plants (liverworts, hornworts, and mosses) that lack vascular tissue and move water and dissolved nutrients by diffusion


the female reproductive structure of a flower


an outer waxy layer over the leaf and stem surfaces of plants to keep moisture inside their tissues


organisms that break down and feed on once-living organisms

double fertilization

two separate fusions of male nuclei from the pollen grain with female nuceli in an ovule to produce an embryo and endosperm


a store of carbohydrate within the seed that fuels the seed's initial growth


supporting stalk of the anther

fleshy fruit

consists of the ovary and some additional parts of the flower that, whose seeds are dispersed by animals after they are eaten


the part of the angiosperm that contains the reproductive structures


the haploid plant structure that produces gametes (sperm and egg)


vascular plants that do not produce their seeds in a protective structure, but are usually found on the surface of the scales of a cone-like structure


long strings of cells that make up the body of a fungus


fungi and chlorophyll-containing bacteria and algae becoming "partners" in mutually beneficial relationships


a mass of interconnecting hyphae that make up the structure of a multicellular fungus


fungi that are in symbiotic associatons with plant roots

non-vascular plant

do not have vessels to transport water and food


enclosed chamber that contains one or more ovules in which eggs develop


the structure within the ovary of flowering plants that gives rise to female egg cells


a multicellular eukaryote that produces its own food by photosynthesis and has an embryo that develops within the protected environment of the female parent

pollen grain

a structure that contains the male gametophyte of seed plants


the transfer of pollen from the male part of the flower (anther) to the ovule (female part) of the flower


the free-living, heart-shaped, haploid life stage of a fern


the part of the plant below ground that is used to obtain water, nitrogen, and salts from the soil


an embryonic plant with its own supply of water and nutrients encased within a protective coating


the part of the plant above ground consisting of the stem and leaves


structures in which the spores are produced


a single cell containing DNA, RNA, and a few proteins that can land in a moist, sheltered spot and grow into new (haploid) male or female bryophytes


the male reproductive structure of a flower

vascular plant

transport water and dissolved nutrients by means of vascular tissue, a system of tubes that extends from the roots through the stem and into the leaves


the protein container surrounding the genetic material (DNA or RNA) of a virus


a layer surrounding the cell wall of many bacteria that may restrict the movement of water out of the cell and thus allow bacteria to live in dry places, such as the surface of the skin


feed on inorganic molecules (ammonia, hydrogen sulfide, iron)


feed on organic molecules (sugars)


the process by which one bacterium transfers a copy of some of its genetic information to another bacterium, even when the two bacteria are different species


archaea and bacteria that can tolerate extreme physical and chemical conditions

Gram stain

a method of dying the cell walls of bacteria to make them visible under a microscope and is helpful in identifying an unknown bacterium


the organism that a parasite lives in or on


any microscopic organism, including bacteria, archaea, and protists

Oxygen Revolution

the accumulation of oxygen released by cyanobacteria beginning 2.6 billion years ago


an organism that lives in or on another organism


any disease-causing organism


a glycoprotein on the outside of the cell wall of some bacteria


relatively large particles are engulfed by the plasma membrane, a vesicle is formed, and the particle is moved into the cell


use energy from sunlight to produce glucose via photosynthesis


circular DNA molecules in bacteria found in addition to the chromosome

probiotic therapy

a method of treating infections by deliberately introducing benign bacteria


a RNA-containing virus that also contains a viral enzyme called reverse transcriptase that uses a strand of viral RNA as a template to synthesize a single strand of DNA


occurs when a virus called a bacteriophage infects a bacterial cell and passes along new genes to the bacterium


the process by which bacterial cells scavenge DNA from their environment

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