2.2-Flow of 2.2-Flow of Energy in an Energy in an EcosystemEcosystem

SPI 1 Interpret a diagram that illustrates energy flow in an ecosystem.

Energy TransfersEnergy Transfers Energy flows from the sun to autotrophs-

organisms that take the energy from organisms that take the energy from

sunlight and convert it into chemical sunlight and convert it into chemical

bonds, forming macromoleculesbonds, forming macromolecules

What 2 macromolecules do organisms

use to store energy?

Energy TransfersEnergy Transfers

Heterotrophs are organisms that eat autotrophs (and often each other) and use the energy stored in macromolecules for themselves

Two categories you need to know:Two categories you need to know: Autotrophs are called Autotrophs are called producersproducers because they because they

produce macromoleculesproduce macromolecules Heterotrophs are called Heterotrophs are called consumersconsumers because because

they consume macromoleculesthey consume macromolecules

There are 4 types of heterotrophs…There are 4 types of heterotrophs…

Heterotrophs which Heterotrophs which consume only plants for consume only plants for energy are called energy are called herbivoresherbivores..

Heterotrophs which Heterotrophs which consume only other consume only other heterotrophs are called heterotrophs are called carnivorescarnivores

A heterotroph which consumes A heterotroph which consumes both plants and animals are both plants and animals are called called omnivoresomnivores..

A A detritivoredetritivore eats fragments of eats fragments of dead matter in an ecosystem. dead matter in an ecosystem. break down dead organisms by break down dead organisms by

releasing digestive enzymes.releasing digestive enzymes.

Trophic LevelsTrophic Levels Trophic levels refer to an organism’s

position in the sequence of energy transfers within an ecosystem.

Most ecosystems only contain 3 or 4 trophic levels. Level 1 = Producers Level 2 = Herbivores/Omnivores/Detrivores Level 3 = Carnivores/Omnivores/Detrivores

Food ChainsFood Chains A food chain is a simple model that

shows the flow of energy through trophic levels.

Food WebFood Web A food web is a model which

represents the many interconnected food chains and pathways in which energy flows.