1. Lesson Overview Lesson Overview Energy Flow in Ecosystems -Biotic v. Abiotic Factors -Trace the flow of energy through living systems. -Identify the three types of ecological pyramids. -Intro to the Carbon Cycle

2. Lesson Overview Lesson Overview Energy Flow in Ecosystems Biotic Factors A biotic factor is any living part of the environment.

3. Lesson Overview Lesson Overview Energy Flow in Ecosystems Abiotic Factors An abiotic factor is any nonliving part of the environment.

4. Lesson Overview Lesson Overview Energy Flow in Ecosystems Food Chains A food chain is a series of steps in which organisms transfer energy by eating and being eaten.

5. Lesson Overview Lesson Overview Energy Flow in Ecosystems Food Webs In most ecosystems, feeding relationships are much more complicated than the relationships described in a single chain because many animals eat more than one kind of food. Ecologists call this network of feeding interactions a food web.

6. Lesson Overview Lesson Overview Energy Flow in Ecosystems Trophic Levels Each step in a food chain or food web is called a trophic level. Primary producers always make up the first trophic level. Various consumers occupy every other level.

7. Lesson Overview Lesson Overview Energy Flow in Ecosystems Ecological Pyramids Ecological pyramids show the relative amount of energy contained within each trophic level. The different types of ecological pyramids are pyramids of energy and pyramids of biomass.

8. Lesson Overview Lesson Overview Energy Flow in Ecosystems Pyramids of Energy What limits the number of trophic levels is the amount of energy being passed on. Only ~10% of the energy available within one trophic level is transferred to the next trophic level.

9. Lesson Overview Lesson Overview Energy Flow in Ecosystems Pyramids of Biomass The total amount of living tissue within a given trophic level is called its biomass. A pyramid of biomass illustrates the relative amount of living organic matter at each trophic level.

10. Lesson Overview Lesson Overview Energy Flow in Ecosystems Primary Producers Plants, algae and certain bacteria can capture energy from sunlight and convert it into forms they can use. These organisms are called autotrophs. Autotrophs are also called primary producers. Primary producers store energy in forms that make it available to organisms that eat them.

11. Lesson Overview Lesson Overview Energy Flow in Ecosystems Consumers Organisms that must acquire energy from other organisms by ingesting in some way are known as heterotrophs. Heterotrophs are also called consumers.

12. Lesson Overview Lesson Overview Energy Flow in Ecosystems Types of Consumers 1. Carnivores kill and eat other animals. 2. Scavengers are animals that consume dead animals. 3. Decomposers chemically breaking down organic matter. 4. Herbivores eat plant leaves, roots, seeds or fruits. 5. Omnivores eat both plants and animals. 6. Detritivores feed on things broken down by decomposers, often breaking them into smaller pieces.

13. Lesson Overview Lesson Overview Energy Flow in Ecosystems The Carbon Cycle The carbon cycle is one of the most important cycles on Earth and allows for carbon to be recycled and reused throughout the biosphere and all of its organisms.