Biology Ecology

Ecology

the study of the interactions of living organisms with one another and with their physical environment

organism

an individual living thing

ex. black bat

population

all of the individuals of a species that live in the same area

ex. the black bats

community

a group of different species that live together in one area

ex. black bats, worms, moss, etc.

habitat

place where an organism usually lives

ex. cave

ecosystem

the different species plus the environment; biotic factors and abiotic factors

ex. soil in that cave, light entering the cave, temperature in cave, humidity in cave, etc.

biome

major regional or global community of organisms characterized by the climate conditions and the plant communities that thrive there

biotic factors

organisms in a habitat

abiotic factors

physical aspects of the habitat

biodiversity

the assortment or variety of living things in an ecosystem

biodiversity is threatened by

pollution

global warming

habitat destruction

keystone species

a species that has an unusually large effect on its ecosystem

ex. sea otters

producers provide

energy for other organisms in an ecosystem

producer

organism that obtains energy from nonliving resources; organism that makes its own food

autotroph

another word for producer; self feeder

consumer

organism that gets its energy by eating other living or once living resources

heterotroph

another word for consumer; different feeder

producers are

basis for ecosystems energy

most rely on sunlight

almost all obtain energy from sunlight

photosynthesis

herbivores

organisms that eat only plants

ex. rabbits

carnivores

organisms that eat only animals

ex. snake

omnivores

organisms that eat both plants and animals

ex. chicken, humans

detritivores

organisms that eat dead, organic matter

ex. millipede

decomposers

organisms that break down organic matter into simpler compounds

ex. fungi and bacteria

food chain

sequence that links species by their feeding relationships

trophic levels

levels of nourishment in a food chain

ex. producer>herbivore>carnivore

producers level

level 1 on the trophic levels

primary consumers level

level 2 on the trophic levels

herbivores and omnivores

secondary consumers level

level 3 on the trophic levels

carnivores and omnivores

tertiary consumers level

level 4 on the trophic levels

carnivores that eat carnivores and some omnivores

food web

model that shows the complex network of feeding relationships and the flow of energy within and sometimes beyond an ecosystem

pyramid models

an energy pyramid shows the distribution of energy among trophic levels

10% rule

at each trophic level, the energy stored is about 10% of that stores by the level below

biomass

measure of the total dry mass of organisms in a given area

incorporated into the body of a consumer

energy pyramids

the longer a food chain, the more energy lost

diagram that compares energy used by producers, primary consumers, and other trophic levels

ecological niche

how an organism lives in its habitat

-includes all of the physical, chemical, and biological factors that a species needs to survive, stay healthy and reproduce

competition

when 2 organisms fight for the same limited resource

predation

process by which one organism captures and feeds upon another organism

symbiosis

close long term relationship between two or more species that can be beneficial or harmful

-mutualism

-commensalism

-parasitism

mutalism

both benefit

ex.ants and acacia tree

commensalism

one benefits, the other is neither harmed nor helped

ex.whale and barnacle

parasitism

one benefits, the other is harmed

ex.dog and flea

predation and competition

-promote biodiversity

-biologically diverse ecosystems are more stable than ecosystems with fewer species

competitive exclusion

when 2 species compete for the same resource, the one that is better adapted will occupy the niche while the other is either pushed into a less favorable niche or goes extinct

ex.trees

biogeochemical cycle

movement of a particular chemical through the biological and geological, or living and nonliving, parts of an ecosystem; changes of state may occur

hydrologic cycle

the water cycle

precipitation

water that falls to the earth

groundwater

water that seeps into the ground or becomes part of larger bodies of water on the surface

evaporation

water going into the atmosphere as water vapor

transpiration

type of evaporation

evaporation off the surface of leaves

condensation

water vapor to water

elements essential for life

carbon, nitrogen, phosphorus, and sulfur

carbon cycle

carbon is the key to the structure of all organisms on our planet, essential for making carbohydrates, proteins, fats, and nucleic acid

abiotic portion of the cycle

-carbon dioxide gas released in the atmosphere

-bicarbonate dissolved in water

-fossil fuel burning

-soil

biotic portion of the cycle

-cellular respiration produces carbon dioxide as a waste product

-photosynthesis uses the carbon in the carbon dioxide to make sugar

-carbohydrates stored in the plant are then used by the plant in cellular respiration or by a consumer when the plant is eaten

-decomposition also releases carbon

-fossil fuel formation

-methane gas also returns carbon to the atmosphere from decomposition processes

carbon sink or reservoirs

area that stores carbon over a long period of time

human disruption of the carbon cycle

cars, factories, and power plants burn fossil fuels and add carbon dioxide to the atmosphere

natural disruption of the carbon cycle

-forests lock carbon away, but naturally occurring forest fires release that carbon

-volcanic eruptions release carbon dioxide and nitrogen gases that overload normal cycles

nitrogen cycle

-78% of atmosphere is nitrogen gas

-organisms use nitrogen in the form of ions not in the form of N2