Food Chains Shows the steps of energy transfer

Food Chains Shows the steps of energy transfer within an ecosystem. Each step is called a trophic level.

Abiotic vs. Biotic • Factors in a food chain and an ecosystem can be either abiotic or biotic. • Biotic: living (or once-living) • Animals, plants, dead organic matter • Abiotic: non-living (was never alive) • Sun, water, air, soil acidity, pollution, etc.

ALL FOOD CHAINS START WITH ENERGY FROM THE SUN Is the sun a biotic or an abiotic factor?

Key Terms • Producer: Anything that can make it’s own energy through photosynthesis (mostly plants) • Producers are also called “Autotrophs” • “Auto” = self and “Troph” = energy, so they make energy for themselves • Consumer: Anything that must eat it’s food to get energy • • Primary Consumers eat the producers Whatever eats the primary consumer is called the secondary consumer Whatever eats the secondary consumer is called the tertiary consumer Consumers are also called “Heterotrophs” • “Hetero” = different and “troph” = energy, so they get their energy from different sources

• Decomposers: organisms that obtain their energy by breaking down dead organic matter (anything that was alive…. leaves, animals, etc. ) and returning it to the soil • Example: Fungi • Decomposers are a type of heterotroph because they still rely on other sources of food for their energy

Food Webs • A network of complex interactions formed by the feeding relationships among various organisms in an ecosystem • AKA: a bunch of food chains joined together to show all the possible food chains possible in an ecosystem