CH.4 Terms- Env Sci

Ecology

Ecology

the study of how organisms interact with each other and their non-living env.

Species

a group of individuals that are closely related and can mate to produce fertile offspring.

Population

members of the same species that live in the same place at the same time.

Community

all of the diff't populations in a certain area.

Ecosystem

all of the living things and their physical env within a particular area.

Biotic factors

Parts of an ecosystem that are living or used to be living

Abiotic Factors

parts of an ecosystem that were never alive

Habitat

The specific environment in which an organism lives

Resource

anything an organism needs to survive and reproduce.

Pop. density

A measure of how crowded a population is

Pop. distribution

How organisms are arranged within an area

Random distribution

Organisms arranged in no particular pattern

Uniform distribution

Organisms evenly spaced

clumped distribution

Organisms grouped near resources

What is the most common type of distribution in nature?

clumped

sex ratio

how many males vs. females there are in a population

mortality

the rate at which individuals die in a population

natality

the rate at which individuals are born

Immigration-

individuals moving into a population.

Emigration-

individuals moving out of a population.

Migration-

seasonal movement into and out of an area.

Carrying capacity-

the largest pop. size a given env. can sustainably support or handle.

Density-dependent factors:

factors that increase with an increase in population density.

Density-independent factors:

factors that do not change with population density.

Biotic potential-

The maximum number of offspring an organism can produce in ideal conditions.

gestation time-

how long it takes for embryo or fetus to develop and be "born"

generation time-

the time from an organism's birth to the time it has its own offspring

What type of population distribution would you expect to see in territorial animals?

uniform

Is a dead organism biotic or abiotic?

biotic

Sunlight is an example of an _______ factor.

abiotic

A flood killing plants in an area would be a density _________ cause of death.

independent

Disease spreading quickly through a packed population of organisms would be an example of a density _____ cause of death.

dependent