Energy in Ecosystems Organisms interact in order to obtain energy and resources necessary to survive.

Autotrophs Organisms that make their own food. Auto = self Also called Producers

Heterotrophs Depend on other organisms for food and energy. Hetero = other Also called consumers

5 Types of Heterotrophs

Herbivores Eat only plants/autotrophs

Carnivores Eat other heterotrophs

Scavengers/Detrivores Consume organisms that are already dead

Omnivores Eat both animals and plants omni = all

Detritivores/ Decomposers Absorb nutrients from dead organisms; break down decaying matter Fungus, Bacteria

Quick Review

What do you call an organism that can make its own food? What direction does energy flow thru an ecosystem? What do you call an organism that eats both animals and plants? What do you call an organism that absorbs nutrients from dead organisms? autotroph Producer  consumer omnivore detrivore

Energy Flow Energy flows thru an ecosystem in one direction: sun autotroph heterotroph

Food Chain A model that shows how matter and energy move through an ecosystem. arrows show the direction energy is being transferred.

FOOD CHAIN

Trophic Level A feeding step in a food chain that represents each organism.

Can you name the trophic levels below?? Tertiary consumer Primary consumer Producer Secondary consumer

Food Web Shows all the possible feeding relationships at each trophic level in a community.

What’s wrong with this food web?

How do Toxic Chemicals Affect Food Chains & Food Webs?

Toxic Chemicals Nonbiodegradable materials CANNOT be broken down, remain in environment indefinitely

Toxic Chemicals Biological magnification concentration of harmful nonbiodegradable substance increases in organisms as move up food chain

Biomagnification of DDT Video

Ecology pyramids Diagram that shows the relative amounts of energy or matter contained within each trophic level in a food chain or food web. 3 types

Pyramid of energy Pyramid of Energy Heat 0.1% Consumers 1% Consumers 10% Consumers 100% Producers Parasites, scavengers, and decomposers feed at each level. Only about 10% of energy available within one trophic level is transferred to organisms at the next trophic level

Pyramid of numbers Based on the number of individual organisms at each trophic level Pyramid of Numbers Fox (1) Birds (25) Grasshoppers (250) Grasses (3000)

Pyramid of Biomass The total amount of living tissue within a given trophic level is called biomass. Represents the amount of potential food available for each trophic level in an ecosystem.

Energy Transfer and Tropic Levels Video