1. Ecology: Chapter 3

2. What is Ecology? Ecology – study of interactions among organisms and between organisms & their environment All living things depend on each other to survive CIRCLE OF LIFE IDEA

3. Levels of Organization Scientists study Ecology by examining interactions on every level 1. Species – organisms that are so similar to one another that they can breed and produce offspring 2. Populations – group of individuals of the same species that live in the same area 3. Communities – different populations that live in a defined area 4. Ecosystems – all living organisms that live in a particular place together with their non-living environment 5. Biome – group of ecosystems that have the same climate & similar dominant communities 6. Biosphere – extends 8 km above the surface & 11 km below the surface of the ocean

4. Copyright Pearson Prentice Hall Levels of Organization Ecosystem Community Population Individual Biome Biosphere

5. Producers AUTOTROPHS: Organisms that can use sunlight or inorganic chemicals to make their own food Producers are the base (or bottom) of all food chains & webs Examples: Plants, Some Algae, Certain Bacteria

6. Photosynthesis Process of converting sunlight into energy sunlight 6CO 2 + 6H 2 O C 6 H 12 O 6 + 6O 2 Carbon dioxide water carbohydrates oxygen Main Autotrophs that use photosynthesis: 1. land = plants 2. water = algae 3. wet ecosystems = cyanobacteria (photosynthetic bacteria)

7. Chemosynthesis Process of converting chemicals into energy Hydrogen Sulfide + Oxygen = sulfur compounds ↓↓↓ Chemical Energy ↓↓↓ bacteria make CHO using carbon dioxide from sea water Chemosynthetic Bacteria perform this process Found in very remote places 1. volcanic vents on the deep ocean floor 2. hot springs in Yellowstone Park (Old Faithful)

8. Consumers HETEROTROPHS: Organisms that rely on other organisms for their energy and food Many different types: 1. herbivores – eats only plants 2. carnivores – eats only animals 3. omnivores – eats plants & animlas 4. detritivores – eat plant & animal remains & other dead matter 5. decomposers – breaks down organic matter

9. What kind of a Consumer Am I?

10. Feeding Relationships When an organism eats another energy moves from the eaten to the eater Energy flows in one direction thru an ecosystem Sun or inorganic chemicals>> autotrophs >>> heterotrophs Food Chain – a series of steps in which organisms transfer energy by eating and being eaten Food Webs – a network of complex feeding interactions between many organisms - links all the food chains in an ecosystem together

11. Trophic Levels Each step in a food chain or food web Each consumer depends on the trophic level below it for energy Producers/Autotrophs ALWAYS make up the 1 st level Consumers make up all other levels

12. Food Chain

13. autotrophs 1 st level consumer (herbivores) 2 nd level consumer (carnivores) 3 rd level consumer (carnivores) Top level consumer Food Web