ECOSYSTEMS

FOOD CHAINS AND WEBS

ENERGY FLOW IN ECOSYSTEMS

• The greatest amount of energy is in the bottom level- or the producers

• Producers are photosynthetic

PRODUCERS

• Photosynthetic

• Contain most of the energy in a food web

• Autotrophic-make their own food

PRIMARY CONSUMERS

• Eat producers

• Herbivores-eat plants only

• Heterotrophic-get energy from food source

• Often prey animals-hunted by predators

SECONDARY CONSUMER

• Often eats primary consumer and producer

• Omnivore- eats meat (insects are meat) and plants

• Heterotrophic

• Could also be a small

carnivore

TERTIARY CONSUMER

• Usually top of the food chain

• Carnivore- eats meat only

• Predator- hunts prey

• Has no natural predators

SCAVENGERS

• Eat animals that are already dead.

• Do not usually hunt prey.

DECOMPOSERS

• Eat dead and decaying plant and animal matter and waste.

• Examples: Bacteria and Fungi

PREDATOR

• Organism that actively hunts prey.

• In the animal Kingdom, predators often have eyes on the front of their heads for better visual acuity.

PREY

• Organisms that are hunted by predators.

• In the animal kingdom, prey animals often have eyes on the sides of their heads for better peripheral vision.

SYMBIOTIC RELATIONSHIPS

• Long-standing relationships between organisms in an ecosystem

MUTUALISM

• Relationship where both organisms benefit

COMMENSALISM

• Relationship where one organism benefits, and the other is unaffected.

PARASITISM

• Relationship where one organism benefits and the other is harmed.

• Examples: mosquitoes, ticks, tapeworms

FOOD WEBS

Interconnected organisms in an ecosystem.

The arrow is always pointing to the thing doing the eating!

VOCABULARY

• Producer Mutualism• Primary consumer Commensalism• Secondary consumer Parasitism• Tertiary consumer Predator• Herbivore Prey• Carnivore Scavenger• Omnivore Decomposer• Autotroph• Heterotroph• Symbiosis

Teacher Notes

• Begin with BrainPop- category: “Ecology and Behavior”, videos: “Ecosystems”, “Food Chains”, “Symbiosis”

• This vocabulary is heavily TAKS tested, so the students need lots of practice making connections between the terms.

• Have the students take notes on the power point, then have them define the vocabulary at the end.

• Have the students create a food chain and food web based on organisms from either a desert environment, a forest environment, or a marine environment. They must have a producer, primary consumer, secondary consumer, tertiary consumer.

Continued…..• Have students group organisms in categories of:

autotrophs, heterotrophs, consumers, producers, omnivores, herbivores, carnivores. Example:

• Carnivores are also: predators, consumers, heterotrophs.

• Autotrophs are also: producers, photosynthetic, bottom of the food chain.

• Have students turn in webs and classifications to their science teacher for extra credit!