Energy Flow in Ecosystems

Energy Roles *Every organism has a role in the movement of energy through an ecosystem. *All organisms will be either a producer, consumer, or decomposer.

Feeding Relationships Producer- all autotrophs (they can make their own food) they trap energy from the sun and go through photosynthesis they are always at the bottom of a food chain Examples include: plants, algae, and some bacteria How do they trap the sun’s energy? Through what process? What is that process similar to in animal cells?

Feeding Relationships Consumer- Decomposers Breakdown the complex compounds of dead and decaying plants and animals into simpler molecules that can be absorbed Ex: FBI: fungi, bacteria, and insects Humans and bears are omnivores but a large and important subset of omnivores are the decomposers. They breakdown dead producers and release the energy back into circulation.

Feeding Relationships Consumer- all heterotrophs they ingest food Examples: Herbivores: eat only plants (Ex: cow) Carnivores: eat only animals (Ex: lion) Omnivores: eat both plants and animals (Ex: bear) Scavengers: a carnivore that feeds on the bodies of dead organisms (Ex: vulture or ant) Energy moves up the food chain through the producer/consumer relationship.

Trophic Levels Each link in a food chain is known as a trophic level. Trophic levels represent a feeding step in the transfer of energy and matter in an ecosystem.

Trophic Levels Food chain- simple model that shows how matter and energy move through an ecosystem

Trophic Levels Food web- shows all possible feeding relationships in a community at each trophic level Represents a network of interconnected food chains

Food chain Food web (just 1 path of energy) (all possible energy paths)

ENERGY PYRAMID- a diagram that shows the amount of energy that moves from one feeding level to another. The most energy is available at the producer level. (bottom) The amount of energy decreases as you go up. Only 10% of the energy moves to the next level.

E N R G Y Producers- Autotrophs Trophic Levels Tertiary consumers- top carnivores Secondary consumers- small carnivores Primary consumers- Herbivores Producers- Autotrophs