Energy in EcosystemsMRS. PITTALUGA

8TH GRADE SCIENCE

I can… Identify food chains within food webs and label the trophic levels to which each organism belongs.◦ NC Essential Standard – 8.L.3.3: Explain how the flow of

energy within food webs is interconnected with the cycling of matter (including water, nitrogen, carbon dioxide, and oxygen)

producers

• An organism that makes its own food through a chemical reaction – photosynthesis or chemosynthesis

• Also called autotrophs

consumers• An organism that consumes

other organisms for food• Heterotrophs• Herbivores, Carnivores,

Omnivores

decomposer

Organisms that break down the remains of dead

organisms and other organic waste

Food Chain◦ Diagram that shows how

matter and energy move through an ecosystem

◦ Grass Rabbit Snake Hawk─ Arrows show direction the

energy is moving─ Food chains always start with a

plant─ Usually have only 3-5 levels─ Energy is lost when moving up

the food chain.

Trophic Levels:◦ The level an organism belongs

to is determined by its distance from the producer

◦ 1st Trophic Level – Producers◦ 2nd Trophic Level – Primary

consumers◦ 3rd Trophic Level – Secondary

consumers◦ 4th Trophic Level – Tertiary

consumers

Food Web◦ More complex than a food

chain◦ Shows all the possible

feeding relationships at each trophic level in a community─ More realistic than a food

chain─ Most heterotrophs depend on

more than one species for food or energy.

I can… Interpret an energy pyramid to determine what happens (and why it happens) to the amount of energy as you move up the trophic levels.

The Energy Pyramid• The energy pyramid

is a visual representation of the flow of energy within a community.

• It is designed to show the amount of biomass at each trophic level.

• Biomass is the amount of living or organic matter within an organism

10% Rule of Ecology

An average of only 10% of the energy in one trophic level is passed to the next trophic level.

Energy Pyramid Foldable