A series of organisms, beginning with green organisms, in which each organism feeds upon the one before it in the series
Food chain
All members of the same species living in a particular area
Population
Simple green organisms that have chlorophyll but lack roots, stems, and leaves
Algae
All things living together in a given area
Community
The branch of biology that studies the relationship between living things and the environment
Ecology
Organisms, such as a green plant or alga, that use light energy to make food; the first organism in every food chain
Producers
In a food chain, the term that means the organisms that feed on plants or other producer organisms
First level consumers
In a food chain, the term for an animal that feeds on animals that eat plants
second-level consumer
An organism that obtains nutrients by breaking down, or decaying, the remains or wastes of living things
decomposer
All the interconnecting food chains of an area; consists of many producer, consumer, and decomposer organisms
food web
Parasites found in the digestive tracts of various animals. It has a head equipped with hooks or suckers to securely attach it to the digestive tract
tapeworms
The organism a parasite lives on or in
host
symbiotic relationship in which both species benefit from the relationship
mutualism
An organism that lives on or inside another organism (the host) from which it gets its food. It can harm or even kill the host.
parasite
A common demand by two or more organisms upon a limited supply of a resource; for example, food, water, light, space, mates, nesting sites.
competition
One group of simple non-green organisms; has no chlorophyll, no roots, no stems, and no leaves; group includes yeasts, molds, and mushrooms
fungus
A close relationship between two species that benefits at least one of the species
symbiosis
A certain type of organism composed of cells of an alga and a fungus; Organisms consisting of a symbiotic relationship of a fungus with a photosynthetic partner (green algae). Both organisms benefit from each other.
lichens
Chemical substances that keeps plants healthy-need to be constantly replaced.
nitrates and phospates
Matter that is part of living thing or has been produced by a living thing
organic matter
Organic matter composed of animal wastes, fallen leaves, and bodies of plants and animals; it enriches the soil.
humus
The gradual replacement of the organisms in a community by new organisms, which make up another kind of community
succession
The circulation of carbon dioxide and oxygen between the atmosphere and living things
carbon dioxide-oxygen cycle
The circulation of water between the water vapor of the atmosphere and the liquid water of the surface of the earth; includes water taken in and given off by living things.
water cycle
Term for when materials are exchanged over and over between living and nonliving things.
cycles