1. Nutrition and Energy Flow

2. Where does this energy come from?
All living things require energy to carry out life processes
Where does this energy come from?

3. The Sun!
autotrophs – absorb solar energy; make own nutrients (plants, bacteria, protists)
Phototrophs
Chemotrophs
Heterotrophs – gain energy through consumption (herbivore, carnivore, omnivore, decomposer → detrivore, saprophyte)

4. Energy Transformation
Light Energy
Chemical energy
Free Energy (ATP)

5. Cycle of Energy Photosynthesis
H2O & CO2 + light → C6H12O6(glucose) + O2
Used by autotroph and passed to other organisms

6. Cycle of energy

7. Food Chains
Arrows point toward recipient of energy

8. Food webs
Model of many interconnected food chains

9. Trophic levels
One organism can occupy several levels; size of step illustrates # organisms

10. Biomass – total living matter at level
Pyramid of Energy
10% Rule: 10% energy transferred at each trophic level → energy used for metabolism & tissue building
Biomass – total living matter at level

11. Example