4 Ecosystems and Energy Flow Free Online FlashCards

What is an ecosystem?

An ecosystem is a community of organisms and the nonliving environment with which they interact.

How do biotic and abiotic ecosystem components differ?

Biotic components are living organisms; abiotic components are nonliving conditions and materials, such as water, sunlight, soil, and temperature.

How do producers obtain energy to make organic molecules?

Producers make organic molecules using sunlight or, in some ecosystems, energy from chemical reactions.

How do consumers obtain energy, and what distinguishes the three consumer types?

Consumers obtain energy by eating other organisms. Herbivores eat producers, carnivores eat other consumers, and omnivores eat both.

What do decomposers do in an ecosystem?

Decomposers break down dead organisms and waste, releasing nutrients back into the environment for reuse by producers.

What does an arrow in a food chain show?

The arrows point from the organism being eaten to the organism that eats it, showing the direction of energy transfer.

What does a food web show that a single food chain does not?

A food web combines many connected food chains, showing a more realistic picture of feeding relationships.

What is a trophic level?

A trophic level is an organism’s feeding position in a food chain or food web.

What do the first four trophic levels represent?

Primary producers are the first level; primary consumers eat producers, secondary consumers eat primary consumers, and tertiary consumers eat secondary consumers.

Why can a species occupy different trophic levels?

A species can feed at different trophic levels depending on what it eats.

How does energy move through an ecosystem?

Energy flows one way: it enters mainly as sunlight, passes among organisms, and eventually dissipates as heat.

Why is not all acquired energy available as biomass to the next trophic level?

Organisms use much of their acquired energy for life processes such as movement, growth, and maintaining their bodies, so it does not become new biomass for the next level.