AP Biology Unit 8: Ecology

A list of selected terms from Unit 8 taken from the Princeton Review book for AP Biology.

endotherms

animals that regulate their body temperature through bodily processes

ectotherms

animals that regulate their body temperature via external mechanisms

behavior

an organism's response to its environment

learning

a change in behavior due to experience

agonistic behavior

aggression resulting from competition for food or other resources

dominance hierarchy

a phenomenon in which members in a group have established which members are most dominant

territoriality

a behavior used when food and nesting sites are in short supply; to protect resources

altruistic behavior

unselfish behavior that benefits another organism in a group at the expense of the individual

symbiotic relationship

a relationship between two species that coexist

mutualism

symbiosis in which both species benefit

commensalism

symbiosis in which one species benefits but the other is unaffected

parasitism

symbiosis in which one species benefits but the other is harmed

photoperiodism

a plant's response to changes in the amount of daylight they receive

phototropism

a plant's response to light

gravitropism

a plant's response to gravity

thigmotropism

a plant's response to touch

auxins

plant hormones that influence a plant's response to their environment (e.g., phototropism)

ecology

the study of interactions between living things and their environments

population

a group of individuals that belong to the same species that are interbreeding

community

a group of populations interacting in the same area

ecosystem

the interaction of living and nonliving things

biosphere

the entire part of Earth where living things live

biotic factors

also known as living factors

abiotic factors

also known as nonliving factors; includes the environment

niche

an organism's position, function, or role in a community

food chain

a diagram that describes the way different organisms depend on one another for food

producers/autotrophs

organisms that make their own food

primary productivity

the rate at which autotrophs convert light energy into chemical energy in an encosystem

heterotrophs

organisms that get energy by consuming food

decomposers

organisms that break down organic matter into simple products

keystone species

an organism that is particularly important to an ecosystem

bioaccumulation

the accumulation of a substance, particularly a toxin, within an organism

biomagnification

the increasing concentration of a toxin in successive trophic levels

carrying capacity

the maximum numbers of individuals of a species that a habitat can support

primary succession

ecological succession of a habitat from a bare environment

secondary succession

ecological succession of a habitat from previous destruction