Biology Unit 5

Examining geographic range

a place where a population lives

Growth rate

how fast a population grows

Density & distribution

1. random

2. uniform

3. clumped

Age structure

distribution via age

How does a population grow?

logistic growth

Density-dependent factors

competition, stress from overcrowding, parasitism, disease, predation, herbivory

Density-independent

environmental extremes, unusual weather, natural disasters, artificial control measures

Biome

a region characterized by resident life/environment

Ecosystem

an interaction between organisms in an environment

Habitat

specific to a species population

Keystone species

maintains balance of trophic levels

Microhabitats

tiny part of a larger habitat with its own set of environmental conditions

Niche

a range of physical/biological conditions which species survive and reproduce

Fundamental niche

a range species could potentially inhibit

Realized niche

the actual range for which a species inhibit

Competitive exclusion principle

2 species cannot coexist indefinitely in the same ecological niche

Species interactions

competition, predation/herbivory, parasitism (+/-), mutualism (+/+), commensalism (+/0)

Primary succession

a series of predictable changes that occur in an area where no soil organisms exist

Secondary succession

a series of changes that occur in an area where an ecosystem is disturbed, but soil and organisms already exist

Ecosystem services

Provisional, regulatory, supporting, cultural

Global hectares (gha)

a standardized unit used to measure both the ecological footprint (demand on nature) and the biocapacity (availability of resources) of the planet

Biocapacity

an ability of a biologically productive area to generate renewable resources to clean up its waste

Anthromes

human-altered biomes, long-term

Greenhouse gases

CO2, methane, nitrous oxide, etc.

Ocean acidification

CO2 dissolved in water

Biological magnification

a pollutant is highly concentrated in organisms at higher trophic levels