IB ESS Topic 2.2

Front

What is a keystone species?

Back

A species in an ecosystem that plays a central role in the health of that ecosystem, and whose removal may cause the collapse of the ecosystem.

Front

What do the arrows in a food chain or web represent?

Back

They show what direction the energy is flowing between organisms.

Front

What is an autotroph?

Back

An organism that uses sunlight to create its own food.

Front

What is a heterotroph?

Back

An organism that cannot produce its own food and must consume other organisms for energy.

Front

What is a consumer in an ecosystem?

Back

An organism that obtains energy by consuming other organisms.

Front

What is a decomposer?

Back

An organism that breaks down dead organic material, returning nutrients to the ecosystem.

Front

What is carrying capacity?

Back

The largest number of individuals of a population that an environment can support.

Front

What is a food web?

Back

A complex network of feeding relationships among organisms in an ecosystem.

Front

What is a food chain?

Back

A linear sequence of organisms through which nutrients and energy pass as one organism eats another.

Front

What is a limiting factor?

Back

A resource or condition that limits the growth, abundance, or distribution of a population.