1. Ecology
Energy and Food chains

2. Energy Flow in Ecosystems
Organisms require a constant source of energy to survive

3. Energy flow in Ecosystems
Energy flows through an ecosystem in one-direction
FIRST LAW of THERMODYNAMICS:
Energy can be converted from one form to another, but cannot be created or destroyed.
SECOND LAW of THERMODYNAMICS:
Transformations of energy always result in some loss or dissipation of energy

4. Energy Flow contd
Ultimate source of energy for all organisms is the sun

5. Producers
An organism that converts sunlight energy into chemical energy
Plants are the base of every food chain

6. Consumers Organisms that cannot make their own energy
Herbivore: eats only plants
Ex. Cows, horses
Carnivore: eats only meat
Ex. Polar bear
Onmivore: eats plants and animals
Ex. Humans, grizzly bears
Scavenger: carnivore that eats dead organisms
Ex. Vultures, crows
Decomposers: organisms that recycle nutrients in dead animals and their wastes
Ex. Millipedes, worms, molds, fungus, bacteria

7. Food Chains
The mechanism in which Energy is transferred from one organism to another

8. Food Chains
Starts with a producer and finish with a top carnivore

9. Examples Deer grazes on grass 
energy is transferred from grass to deer

10. Examples
Wolves feed on deer 
energy is transferred from deer to wolf

11. Algae krill cod Leopard Seal  Killer Whale

12. Food Web
- A representation of the feeding relationships within a community
- Interconnecting food chains
(a more realistic view)