Chapter 3-4 Terms

Chapter 3-4 Terms Flashcards

Biotic Factors

Living things in an ecosystem.

Abiotic Factors

The non-living physical surroundings.

Population

A group of organisms of one species that interbreed and live in the same place and time.

Community

Several populations living together.

Ecosystem

All the community and abiotic factors together in the same place.

Biome

A group of ecosystems that share a particular climate and typical organisms.

Biosphere

The part of the Earth where life exists.

Autotrophs

Organisms that use energy from the sun or energy stored in chemical compounds to manufacture their own nutrients. Literally "self-feeders."

Photosynthesis

The chemical process used by photoautotrophs to convert the sun's energy into organic compounds and chemical energy.

Photoautotroph

An autotroph that uses photosynthesis.

Chemosynthesis

The chemical process used by chemoautotrophs to convert inorganic chemicals in the environment into organic compounds and chemical energy.

Chemoautotrophs

An autotroph that uses chemosynthesis.

Heterotroph

Organisms that cannot make their own food and must eat other organisms. Literally "other feeders."

Permafrost

The layer of permanently frozen soil found in tundra.

Photic Zone

The portion of a marine biome that is shallow enough to let light penetrate. Near the coastlines. Photoautotrophs are common.

Aphotic Zone

The portion of a marine biome that includes deep water that never gets sunlight. Consumers, scavengers, and in some places chemoautrophs.

Estuary

A coastal body of water, partially surrounded by land, where freshwater and saltwater mix.

Intertidal Zone

The portion of the shoreline that lies between the high and low tide.

Neritic Zone

Shallow waters between the intertidal and oceanic zones.

Oceanic Zone

Deep, open ocean beyond the neritic zone.

Pelagic Zone

Open water in any of the above zones.

Benthic Zone

The sea floor.

Phytoplankton

Small producer organisms that live in the photic zone.

Zooplankton

Small organisms that feed on phytoplankton.

Scavengers

Organisms that eat animals that have already died or been killed.

Carnivores

Heterotrophs that eat other heterotrophs.

Herbivores

Heterotrophs that eat autotrophs.

Omnivores

Heterotrophs that eat both heterotrophs and autotrophs.

Decomposers

Organisms that break down dead and decaying plants and animals into simpler compounds for energy.

Food chain

An ecological model that shows the path of energy through a community.

Trophic level

A feeding step in a food chain.

Food web

An ecological model that expresses multiple possible energy paths at each trophic level in a community.

Ecological Pyramid

A diagram illustrating the relative amount of energy or matter at each trophic level of a food chain or food web.

10% rule

The general rule that only 10% of the energy on one trophic level is available to the trophic level above.

Biomass

The total quantity of living matter at each trophic level.