1. INTERRELATIONSHIPS OF ORGANISMS

2. LIVING THINGS

3. ENERGY= Capacity to do work or cause change
Free energy = energy actually able to do work
Chemical energy = stored (potential) energy

4. WHY DO WE NEED ENERGY? For metabolism ( chemical)
For movement of nutrients
Mechanical movement

5. HOW DO WE GET ENERGY?
Autotrophs = obtain energy and nutrients from nonliving sources (abiotic)
Heterotrophs = obtain it from other organisms, living or dead

6. HOW?
PHOTOSYNTHESIS = CHEMICAL REACTIONS THROUGH WHICH AUTOTROPHS CAPTURE ENERGY FROM SUNLIGHT AND USE IT TO FORM ORGANIC COMPOUNDS FROM CO2 AND H2O
SOME ENERGY IS STORED AND USED LATER; SOME USED FOR GROWTH, REPAIR AND MAINTENANCE

7. Cellular respiration = series of chemical reactions that convert stored energy to free energy to do cellular work
Both autotrophs and heterotrophs use this process

8. WHAT IS A FOOD WEB? Producers = make food
Consumers = eat plants and other organisms
Decomposers = use dead organisms for food
Abiotic and biotic factors

9. ECOSYSTEM
Interaction of biotic and abiotic components in a given area (pond, forest)
Within each ecosystem, a variety of habitats

10. HOW DOES ENERGY FLOW?
Governed by the laws of thermodynamics (bioenergetics)
1. Energy cannot be created or destroyed but it can be transferred or transformed

11. WHAT DOES THIS MEAN FOR LIVING ORGANISMS?
Must get energy from outside source
Autotrophs -> sun; heterotrophs -> chemical energy stored in food; chemical energy is transformed into free energy, heat is also released

12. 2. Natural processes tend to proceed in a way that increases disorder (entropy) of a system
Energy released as heat is no longer available to do work

13. As free energy decreases, system becomes increasingly disordered
As free energy decreases, entropy increases
As energy flows through a food web, it is eventually released into surroundings as heat

14. THIS ONE WAY ENERGY FLOW MEANS THAT IN ORDER TO AVOID ENTROPY, LIVING ORGANISMS MUST CONSTANTLY OBTAIN ENERGY (FOOD) FROM THEIR SURROUNDINGS