abiotic:  referring to the nonliving factors in the environment.

biotic:  referring to the living factors in the environment.

biome:  A group of ecosystems with similar kinds of climates and similar plant and animal communities.

boreal forest:  relating to, or growing in the northern and mountainous parts of the northern hemisphere.

climate:  weather conditions that an area has over a long period of time.

climax community:  the final stage in succession of plant and animal life of a community.

community:  different kinds of populations living in the same habitat.

cones:  woody structures containing the seeds of cone-bearing plants.

coniferous forest:  a biome in which the environmental conditions favor the growth of cone-bearing trees.

conifers:  cone-bearing plants with needlelike leaves; mostly evergreens.

conservation:  the protection and wise use of the earth's resources.

cycle:  the series of steps in which nonliving materials move through the environment.

deciduous:  describing plants that shed leaves each fall.

deciduous forest:  a biome in which the environmental conditions favor the growth of deciduous trees.

decomposers:  living things that get their food from breaking down the remains of plants and animals or their wastes

desert:  a biome that receives little rainfall.

ecology:  the study of how living things interact with each other and with their nonliving environment.

ecosystem:  a group of communities and their nonliving environment.

endangered:  describing an animal or plant species that is in danger of becoming extinct.

environment:  the surroundings in which a plant or an animal lives.

evergreens:  plants that keep their leaves throughout the year.

extinct:  describing an animal or plant species that no longer exists.

ferns:  flowerless, vascular plants.

food chain:  the flow of energy from producers to consumers in a community.

fronds:  fern leaves that bear spores.

grasslands:  a biome in which the environmental conditions are suitable for the growth of grass but not for most trees.

gymnosperms:  a class of plants that produce seeds that have no outer covering;  mostly conifers.

habitat:  the place where an organism lives.

natural resources:  living and nonliving things that humans remove from their environment for their own use;  for example, plants, animals, water and soil.

nonrenewable resources:  natural resources that can not be replaced or that can be replaced only over a long period of time.

population:  a group of the same kind of organisms living in the same habitat.

producers:  green plants that use the sun's energy to make their own food.

rain forest:  a biome that receives large amounts of rainfall each year and that always has warm temperatures.

renewable resources:  natural resources that can be replaced in a short time.

succession:  the gradual changes in an area during which one community replaces another.

taiga:  moist subarctic coniferous forest that begins where the tundra ends and is dominated by spruces and firs.

wildlife:  wild plants or animals.