Chapter 3.3: Energy Flow in Ecosystems

If 100% of the energy is available at the first trophic level of an energy pyramid, what percentage of that energy is available at the highest trophic level?

0.01% of energy will be left at the highest trophic level.

How does energy flow through ecosystems?

Energy flows through an ecosystem in a 1-way stream, from primary producers to various consumers.

Explain what you think might happen to the Everglades ecosystem if there were a sudden decrease in the number of crayfish.

It would affect the rest of the animals/organisms in the web.

On average, what proportion of the energy in an ecosystem is transferred from 1 trophic level to the next? Where does the rest of the energy go?

On average, about 10% of the energy in an ecosystem is transferred from 1 trophic level to the next. Most of the remaining energy is released into the environment as heat.

Energy is said to flow in a "1-way stream" through an ecosystem. In your own words, describe what that means.

Producers receive chemicals from light rays, 1st-level consumers eat producers, 2nd-level consumers eat 1st-level consumers, and 3rd-level consumers eat 2nd-level consumers.

What do the 3 types of ecological pyramids illustrate?

Pyramids of energy show the relative amount of energy available at each trophic level of a food chain or food web. A pyramid of biomass illustrates the relative amount of living organic matter available at each trophic level in an ecosystem. A pyramid of numbers shows the relative number of individual organisms at each trophic level in an ecosystem.

What are the 3 types of ecological pyramids?

The 3 types of ecological pyramids are the pyramids of energy, pyramids of biomass, and pyramids of numbers.

zooplankton

a diverse group of small, swimming animals

phytoplankton

a mixture of floating algae that are some primary producers in some aquatic food chains

food chain

a series of steps in which organisms transfer energy by eating and being eaten

trophic level

each step on a food chain or food web

ecological pyramids

show the relative amount of energy or matter contained within each trophic level in a given food chain or food web

food web

the network of feeding interactions, a series of food chains

biomass

the total amount of living tissue within a given trophic level