Energy in Ecosystems & Food chains and Food WEbs 13.3 & 13.4

Where does energy come from? THE SUN!!! Producers – get energy from non-living resources Make their own food Also considered “autotrophs” – self nourishment Consumers – get energy from living resources Need to eat stuff Also considered “heterotrophs” – different nourishment

Energy Flow in an Ecosystem

Special cases Chemosynthesizers do not need sunlight to make food Use chemicals in their surroundings Considered chemoautotrophs – chemical self nourishment Examples? Hydrothermal pools/vents, marshy areas

Food chains Links species by their feeding relationship One producer and a single chain of consumers

Types of consumers Herbivores – eat plant matter Carnivores – eat other animals Omnivores – eat both plants and animals Detritivores – eat dead organic matter Decomposers – detritivores that break down organic matter into simpler compounds

Trophic levels Levels of nourishment in food chains Producer – plants Primary consumer – grasshopper Secondary consumer – frog Tertiary consumer – snake Quaternary consumer – hawk

Food webs Shows the big picture Indicates complex feeding relationships and energy flow within an ecosystem Can also sometimes show energy flow beyond the ecosystem