1. Lesson 1.3: Ecological Food Webs

2. Organizational Levels of Ecology:
1. Biosphere: the entire planet, including the land, ocean, and
atmosphere, and all living things = WORLD
2. Biome: a group of ecosystems that share similar climates
and organisms = COUNTRY
3. Ecosystem: a group of communities
with interacting organisms
through which energy is
transferred = STATE

3. Organizational Levels of Ecology:
4. Community: a collection of different populations living and
interacting within an ecosystem = TOWN
5. Population: a group of individuals (same species!) that live
and interact within a community = HOUSE
6. Species: a single organism
= INDIVIDUAL
*Words in RED are the most important
levels to study!

4. Energy Table: *Copy this table!
Type of Organism
Energy Source
Example
Autotroph/Producer
Photosynthesis
Giraffe
Chemosynthesis
Bacteria
Heterotroph/Consumer
Cellular Respiration
Human

5. Ways to Get Energy:
Producers are organisms capable of making their own food
They can accomplish this two ways:
Photosynthesis:
Carbon dioxide + water + sunlight = oxygen + sugar
Chemosynthesis:
Carbon dioxide + water + hydrogen sulfide =
oxygen + sugar + sulfur

6. Ways to Get Energy:
Consumers are organisms that must eat to get their energy
All heterotrophs accomplish this one way:
Cellular Respiration:
Converts food and oxygen into energy
Oxygen + sugar = carbon dioxide + water + energy (*the opposite of photosynthesis!)

8. Ways to Get Energy:
*Only copy what you don’t already know, but you will be tested on them ALL!
Herbivore: eats plants (ex. Giraffe)
Carnivore: eats meat (ex. Great White Shark)
Omnivore: eats plants & meat (ex. Human)
Decomposer: break down dead/decaying material and release energy back into the ecosystem (ex. Bacteria)
Detritivore (or Scavenger): feed on broken down dead/decaying material to consume energy for themselves (ex. Vulture)

9. Energy Flow:
A food chain is a single series of steps in which organisms transfer energy by eating and being eaten.
The arrows point to WHO gets the energy/food!
*An example from the Florida Everglades is shown.

10. Energy Flow:
A food web is a network of multiple feeding interactions within an ecosystem.
*An example from the Antarctic Ocean is shown.

12. Energy Flow:
Ecological Pyramids show the amount of energy contained within each trophic level within a food chain or web
Primary producers will always be the 1st level
Consumers will be all of the next levels above