Key Term

Organism: a living thing

Habitat: an environment that provides a specific organism needs to live, grow, and reproduce

Biotic Factor: a living or once living part of an organism's habitat

Abiotic Factor: a nonliving part of an organism's habitat

Population: all the members of one species living in the same area

Community: all the different populations that live togather in a certain area

Ecosystem: the community of organisms that live in a particular area, along with their nonliving environment

Density: the number of individuals in an area of a specific size.

Limiting Factor: an environmental factor that causes a population to decrease in size. Examples-Food and water, climate and weather, and space and shelter.

Producer: an organism that makes its own food

Consumer: an organism that obtains energy by feeding on other organisms

Decomposer: an organism that gets energy by breaking down biotic wastes and dead organisms and returns raw materials to the soil and water

Food Chain: a series of events in which one organism eats another to obtain energy and nutrients

Food Web: consists of many overlapping food chains in an ecosystem

Energy Pyramid: a diagram that shows the amount of energy that moves from one feeding level to another in a food web.

The Law of Conservation of Mass: The principle that the total amount of matter is neither created nor destroyed during any chemical or physical change.

The Law of Conservation of Energy: The role that energy cannot be created or destroyed.

Evaporation: the process by which molecules at the surface of a liquid absorb enough energy to change to a gas.

Condensation: the change in state from a gas to a liquid.

Precipitation: any form of water that falls from clouds and reaches Earth’s surface as rain, snow, sleet, or hail.