Energy Flow: FOOD CHAINS & WEBS EQ: Explain the difference between a food web and a food chain.

sun eclipse with palm the ultimate energy source

Energy Flow in Ecosystems Energy flows from where into the biological world?

Energy Flow How does the sun’s energy enter the biological world? What is photosynthesis?

Energy Flow The sun’s energy flows into organisms that can change the sunlight into food then into organisms that eat them. This flow is: sunlightproducerconsumer 1consumer 2

PRODUCERS Organisms that can produce their own food (glucose) through photosynthesis. AKA - Autotrophs Ex. Plants, algae and some bacteria sunlightproducerconsumer 1consumer 2

CONSUMERS Organisms that have to eat other organisms to obtain energy. AKA - Heterotrophs Examples: deer, rabbits, cows, mice, lions, humans, hawks, snakes sunlightproducerconsumer 1consumer 2

HERBIVORES Organisms that eat plants Primary Consumers Ex. Cows, caterpillars, bunnies sunlightproducerconsumer 1consumer 2

CARNIVORES Organisms that eat meat (other animals/consumers) Secondary Consumers Ex. tigers, wolves, snakes, hawks sunlightproducerconsumer 1consumer 2

TOP CARNIVORES Top-level carnivores eat secondary consumers; usually nothing feeds on them Tertiary Consumer Ex. killer whale eating a sea lion or hawk eating a snake. sunlightproducerconsumer 1consumer 2 consumer 3

OMNIVORES Consumers that eat both plants and animals Primary and Secondary Consumers Ex. bears and humans

Where do all the dead things go? They are eaten. YUMMMM! They decay. SMELLY! What’s the difference? Is it just a matter of taste? decomposer detritivore

Detritivore vs Decomposers Detritivores and decomposers both feed on the remains of dead plants and animals and other dead matter (detritus) They rely on dead tissues for nutrients. detritivore decomposer

Detritivore vs Decomposers Detritivores eat the remains of dead plants and animals Decomposers breakdown (decay) organic matter and feed on it Crabs, mites, earthworms, snails Bacteria & fungi

Detritivores and Decomposers What is a scavenger? A scavengers is a type of detritivore that feeds on carrion (dead animal remains). Ex. vultures, sharks, maggots, hyenas

Detritivores and Decomposers Decomposers are often called the environmental “recyclers”because…. They decompose excrement, dead bodies and leaf litter, returning nutrients to the physical environment. consumer 3 sunlightproducerconsumer 1 consumer 2 decomposer

Energy Flow The series of steps in which organisms transfer energy by eating and being eaten is called a Food Chain sunlightproducerconsumer 1consumer 2

Food Chains & Food Webs The steps in the transfer of energy from organism to organism in feeding relationships are called Trophic Levels. How does a food chain describe this path of energy? (arrows) producer consumer 1consumer 2consumer 3

Food Chains & Food Webs Name the number of the trophic levels in the food chain below. How do the trophic level numbers correspond with the “eating terms”? producer consumer 1consumer 2consumer 3 Trophic Level 1234

Food Chains & Food Webs Some energy is lost from one level to the next level due to heat energy or metabolism. Only 10% of the energy from one level is passed to the next level!! No trophic level can contain more energy than the level before. producer consumer 1consumer 2consumer 3

Food Chains & Food Webs What vital “recycler” is not shown in this food chain? Upon which organism(s) would it feed? producer consumer 1consumer 2consumer 3 decomposer

Food Chains & Food Webs If all of the snakes in this chain died, what would happen to the hawk? To the decomposers? producer consumer 1 consumer 2 consumer 3 decomposer

Food Chains & Food Webs Most organisms feed on more than one trophic level and feed on several different species at each trophic level. This is a food web.

Arctic Food Web

Rangeland Prairie Food Web