Energy Flow in Ecosystems Food Chains Food Webs

Energy Flow in Ecosystems Food Chains & Food Webs

3 Roles • Producer – Makes its own food – usually plants or one-celled organisms – Algae – Phytoplankton, tiny organisms that live in the ocean – Some types of bacteria • Consumer – Obtains energy from eating other organism – Omnivore, herbivore, carnivore, scavenger • Decomposer – Break down wastes and dead organisms and return the raw materials to the environment – fungi and bacteria

Organisms that make their own food are producers.

Organisms that depend on others for food are consumers. • Herbivores plant eaters

Carnivores - meat eaters

Omnivores - plant and meat eaters

Scavengers - feed off dead organisms

Organisms that break down wastes and dead organisms & return the raw materials to the environment are decomposers.

Decomposer

Food Chain • A series of events in which 1 organism eats another and obtains energy • Shows 1 possible path along which energy can move

Food Chain • Arrows point in the direction of the organism that is eating the other. It means “Is eaten by” • http: //www. woodlandsjunior. kent. sch. uk/Home work/fooodchains. htm • Arrows also show the direction of energy flow.

Food Chain • 1 st organism always a producer • 2 nd organism is a primary consumer that eats the producer – 1 st level consumer (primary consumer) • 2 nd level (secondary) consumer eats the 1 st level consumer • 3 rd level consumer (tertiary) feed on secondary consumers

Food Chain • Position in the food chain is related to size. • Larger organisms are normally further up the food chain than smaller organisms

Food Web • A more realistic way to show energy flow in an ecosystem • Shows many overlapping food chains in an ecosystem

Energy Pyramid • A diagram that shows the amount of energy that moves from 1 feeding level to another in a food web • At each level Energy is lost • Only about 10% of the energy in 1 level is transferred to the next level Where does the energy go?

http: //teach. fcps. net/trt 2/links /foodchain. htm carnivores and omnivores herbivores 1 st level consumer ers uc od pr plants 2 nd level consumer

Energy Pyramid • MOST ENERGY IS AVAILABLE AT THE PRODUCER LEVEL • AT EACH LEVEL THERE IS LESS AVAILABLE ENERGY THAN AT THE LEVEL BELOW

Energy loss from Food Chain/Web • Organisms use the energy they get to survive: – – Movement Body heat Reproduce Carry out Chemical Reactions • Energy passed on is from growth. • The bigger the organism eaten, the more energy the next organism gets.