2 Ecosystems and Ecological Processes Free Online FlashCards

What is an ecosystem?

An ecosystem is a community of living organisms interacting with one another and with their nonliving environment.

What do producers do in an ecosystem?

Producers, or autotrophs, make organic food using sunlight or, in some environments, chemical energy.

Why is energy not recycled in ecosystems?

Energy generally flows in one direction: organisms use it for life processes, and much of it is released as heat rather than recycled.

What do arrows in a food chain show?

A food chain shows one pathway of feeding and energy transfer. Its arrows point from the organism being eaten to the organism that eats it.

How do matter and energy differ in ecosystems?

Matter is recycled between organisms and nonliving reservoirs, while energy flows through ecosystems and is ultimately dissipated as heat.

What are the main steps of the water cycle?

In the water cycle, water evaporates, condenses in the atmosphere, and returns as precipitation; it may then run off, enter soil, or be taken up by organisms.

How does carbon move through ecosystems?

Producers take in carbon dioxide during photosynthesis. Carbon moves through food webs and returns to the atmosphere or water through respiration and decomposition.

How do bacteria contribute to the nitrogen cycle?

Bacteria convert atmospheric nitrogen into forms plants can absorb. Nitrogen moves through food webs and returns to soil and water through waste and decomposition; other bacteria return some to the atmosphere.

How does phosphorus enter soil and water?

Weathering releases phosphate from rocks into soil and water. Organisms take it up, and waste and decomposition return it; runoff can carry phosphate into aquatic ecosystems.

How do biotic and abiotic components differ?

Biotic components are living organisms; abiotic components are nonliving factors such as sunlight, water, air, soil, temperature, and minerals.

How do consumers obtain energy?

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

What role do decomposers play?

Decomposers, including many fungi and bacteria, break down dead organisms and waste, returning nutrients to the environment.