(a)   are often flat and have gently rolling hills, and includ grasses and other flowering plants.

(a)   often have scattered trees and are found in tropical and subtropical areas where seasonal rains, fires, and drought happens.

A (a)   is a region that has little or no plant life, long periods without rain, and extreme temperatures; usually found in hot climates

A (a)   is a treeless plain found in the arctic or on the tops of mountains that is characterized by very low winter temperatures and short, cool summers.

A (a)   is a biome characterized by coniferous forests consisting mostly of pines, spruces, and larches.

A (a)   is dominated by trees that lose their leaves each year; found in areas with warm, moist summers and cool winters.

A (a)   is a terrestrial biome found in temperate regions with warm summers, cool winters, and adequate rainfall to sustain a forest.

A (a)   is found in areas of tropical climate in which there is no dry season; they have more biological diversity than other places on Earth.

An (a)   is a marine biome; huge body of saltwater; covers about 71 percent of Earth's surface.

The (a)   is the zone where ocean meets land; this area is exposed to the air for part of the day.

(a)   : as you move farther away from shore, the water becomes deeper, and the ocean floor starts to slope downward.

The (a)   is the zone in which the sea floor drops sharply; contains the deep water of the open ocean.

The (a)   is the zone that consists of the ocean floor; deepest parts of the ocean that do not get any sunlight and are very cold.

A (a)   is a treeless wetland ecosystem where plants such as grasses grow.

A (a)   is a wetland ecosystem in which shrubs and trees grow.

A (a)   is a large natural stream of water flowing in a channel to the sea, a lake, or another such stream.

A (a)   is a small, narrow river.

An (a)   is a mixture of freshwater draining from the land into salty seawater; home to unique plant and animal communities that have adapted to brackish water.

A (a)   is a small body of still water; shallow enough to support rooted plants.

A (a)   is a large inland body of salt or freshwater surrounded by land.

A (a)   is where an organism live out its life.

A (a)   is the role and position a species has in its environment.

Any necessity of life such as water, nutrients, light, food, or space creates (a)   .

(a)   is an interaction in which one organism captures and feeds on another organism.

The (a)   is the animal that captures, kills, and consumes the prey.

An organism that is captured and consumed is called the (a)   .

An interaction between two species living in the same habitat is called (a)   .

(a)   is a type of symbiosis in which both species benefit.

(a)   is a type of symbiosis in which one species benefits and the other is unaffected.

(a)   is a type of symbiosis in which one species benefits and the other is harmed, but not killed.

A (a)   is an organism that is benefited at the expense of another species.

A (a)   is the organism that is invaded and harmed by a parasite.

A (a)   is an organism that can produce its own food using energy from the sun or inorganic compounds.

A (a)   is an organism that must consume other organisms for food.

An (a)   is a consumer that only eats producers.

A (a)   is a consumer that only eats other consumers.

An (a)   is a consumer that eats producers and consumers.

A (a)   is a consumer that breaks down dead and decaying matter for food.

A series of steps in which organisms transfer energy by eating and being eaten, and that follows a single pathway of energy flow is called a (a)   .

A series of steps in which organisms transfer energy by eating and being eaten, and that follows multiple pathways of energy flow is called a (a)   .

The scientific study of interactions among organisms and between organisms and their environment (or surroundings) is called (a)   .

An (a)   in ecology is a single organism.

A group of organisms so similar to one another that they can breed and produce fertile offspring is called a (a)   .

A group of organisms of one species that interbreed, living in the same place at the same time is called a (a)   .

A collection of interacting populations that live together in a defined area is called a (a)   .

A collection of all the organisms that live in a particular place, together with their nonliving, or physical environment is called an (a)   .

All of the biomes together are called the (a)   . The portion of Earth that supports life. High atmosphere to the bottom of the ocean.