94 terms

AP Environmental Science Unit 2- Ecology

A lot of something.
A relationship between two organisms in which one organism benefits and the other is unaffected
trophic level
Each step in a food chain or food web
tertiary consumer
A carnivore that eats other carnivores.
secondary consumer
A carnivore that eats a herbivore
primary consumer
An organism that eats producers
Interaction among organisms that want the same resource in an ecosystem
A layer of water in which temperature changes rapidly with the depth
tropical rainforest
Hot climate, wet season year-round.
tropical seasonal forest
Hot climate, wet and dry seasons, trees shed leaves during dry season
An area of land that is covered with a shallow layer of water during some or all of the year.
Cold climate, dry season year-round biome. Has permafrost, lots of shrubs
Permanently frozen ground
temperate forest
Moderate climate, wet and dry season, trees shed leaves
Cold winters, moderate summers, forest of coniferous trees.
A wetland ecosystem in which trees grow
Dominated by grasses and scattered trees, close to the equator.
Tiny floating photosynthetic organisms, primarily algae
Ocean area anywhere but the bottom. Made up of photic and aphotic
A wetland ecosystem in which shrubs grow
Coastal wetlands, plants grow in waterlogged saltwater
The densest, coldest water layer in a lake. Isolated from wind. Too dark for photosynthesis, low oxygen.
hot climate, dry season year-round. rich soils. found in the interior of continents
A habitat in which the fresh water of a river meets the salt water of the ocean.
water temperature changing due to wind and sunlight, high photosynthesis, high oxygen
An extremely dry area with little water and few plants, can be hot or cold.
deciduous forest
a biome based on trees that lose their leaves each fall
coral reef
An ocean ridge made up of skeletal remains of tiny sea animals
coniferous forest
Evergreen trees with needles and cones, do not lose leaves.
biome bordering the mediterranean sea; characterized by wet winters and warm dry summers, shrubby --> prone to forest fires
wet muddy ground full of decaying peat moss --> decay process is slow due to low oxygen--> slowly forms peat (used as an energy source) and is the precursor to coal
A group of ecosystems with similar climates and organisms
Bottom-dwelling organisms.
tolerance limits
The limit of a variable at which a particular species cannot survive or is unable to reproduce
Animal defends its territory
A close relationship between two species that benefits at least one of the species.
A situation in which things continue without any major changes or problems
A consumer that primarily eats one specific organism or feeds on a very small number of organisms; disruptions to environment are catastrophic to survival
secondary succession
A type of succession that occurs where an existing community has been cleared by some disturbance that leaves the soil intact.
resource partitioning
The differentiation of niches that enables similar species to coexist in a community
the ability of an organism to recover from stress or pressure
law of tolerance
For each abiotic factor, an organism has a set range of tolerances within which it can survive
realized niche
Part of a species fundamental niche that it actually uses, limited by competition.
primary succession
Process by which a community arises in a virtually lifeless area with no soil
primary productivity
Rate at which organic matter is created by producers in an ecosystem
An organism that obtains energy by feeding on other organisms
An organism that makes its own food (usually through photosynthesis
Converting light (heat energy) into food (chemical energy)
CO2 + H2O --(light energy)--> C6H12O6 + O2
An interaction in which one organism kills another for food.
pioneer species
First species to populate an area during primary succession
An organism that causes disease
natural selection
A natural process resulting in the evolution of organisms best adapted to the environment.
A group of living organisms that can breed and produce fertile offspring.
A symbiotic association in which one organism benefits while the other is harmed.
A relationship between two species in which both species benefit
keystone species
A species that influences the survival of many other species in an ecosystem
intraspecific competition
Competition among members of the same species
interspecific competition
Competition between members of different species
a species with a broad niche that can tolerate a wide range of conditions and can use a variety of resources; highly adaptable to environmental disturbances
exotic species
Non-native species in an area; may take over niches of native species in an area and eventually replace them.
native species
Species that have naturally evolved in an area
fundamental niche
The full potential range of conditions and resources a species could theoretically use if there was no competition from other species
fire-climaxed communities
biome characterized by periodic fires every few years, followed by secondary succession (Chapparal)
Change over time
environmental indicators
A measured variable that can inform a scientist about the state of an environmental system
edge effect
different conditions along the boundaries of an ecosystem
A transitional zone where ecosystems meet. edge effect
Gradual change in organisms that occurs when the environment changes
Full range of physical and biological conditions in which an organism lives and the way in which the organism uses those conditions
A measurement of the number of species inhabiting an ecosystem.
biotic potential
maximum rate at which a population could increase without competition
density dependent factors
A limiting factor of a population wherein large, dense populations are more strongly affected than small, less crowded ones. (food shortages, land, disease)
movement of individuals out of an area
movement of individuals into an area
Death rate
Birth rate
Shows the number of survivors of each age group for a particular species.
S curve
Logistic growth curve. Leveling off of an exponential, J-shaped curve when a rapidly growing population exceeds the carrying capacity of its environment and ceases to grow.
r-selected species
Species that reproduce early in their life span and produce large numbers of usually small and short-lived offspring in a short period; no mothering of their young
population crash
a sudden population decline caused by predation, waste accumulation, or resource depletion
population density
Describes how many individuals are in a certain area.
to exceed the carrying capacity of an area
minimum viable population
The smallest population size at which a species is able to sustain its numbers and survive. Any lower than this, and genetic diversity is too low.
logistic growth
Population growth that is controlled by limited resources.
life expectancy
How long an individual is expected to live
k-selected species
are characterized by producing low numbers of large offspring. They have slow maturation, long gestation periods, parental care and long life in a stable environment. Bigger animals. humans
J curve
a curve representing exponential (unrestricted) population growth
genetic drift
A change in the gene pool of a population due to chance
founder effect
Genetic drift that occurs after a small number of individuals colonize a new area
the ability of a population to reproduce, or soil to support plants
environmental resistance
All of the limiting factors that act together to limit the growth of a population.
density independent factors
Environmental resistance that affects a population regardless of density. (weather disasters)