1. Ecology 101
Energy Transfer

2. The Sun
The sun is the source of energy needed for plants to produce their own food. Therefore, it is the source of energy for almost all living things. In this transfer of energy, living things are divided into two categories: autotrophs and heterotrophs.

3. Autotrophs
organisms that can use the energy in sunlight to produce their own food (glucose)
autotrophs are also called Producers because they produce their own food
all food chains start with an autotroph
examples include plants, algae and some bacteria

4. Chemotrophs
autotrophs that get their energy from inorganic substances, such as salt, iron and sulfur
Ex. Bacteria and Deep Sea Worms

5. Heterotrophs Organisms that do not make their own food
Another term for heterotroph is consumer because they consume other organisms in order to live
There are 5 types of heterotrophs: scavengers, herbivores, carnivores, omnivores and decomposers.

6. Scavengers
– feed on the tissue of dead organisms (both plants and animals); they are also known as detritivores
Ex. – Vultures, Crows, and Shrimp

7. Herbivores – consumers that feed only on plant material
Ex: cows, elephants, rabbits

8. Carnivore – consumers that feed only on meat
Ex: sharks, tigers, wolves

9. Omnivore – consumers that eat both plant and animal material
Ex: bears, raccoons, humans

10. Decomposer
– organisms that consume wastes and dead organisms; they help recycle once-living matter by breaking it down into simple, energy-rich substances.
Ex: fungi and bacteria

11. Energy Transfer
In an ecosystem there is energy, and this is what allows the organisms to live. This energy mainly comes from one original source: the sun. Plants use this solar energy to produce carbohydrates which serves as fuel for living things. When one organism eats another, only some of this energy can be transferred because it has to be used by the organism that was eaten.

12. Conservation of Energy
Energy cannot be created or destroyed, it just changes forms.

13. Food Chains
The energy flow from one trophic (feeding) level to the other is known as a food chain
A food chain is simple and direct. It involves one organism at each trophic level

14. Trophic Levels
Producer – produce their own food

15. Trophic Levels
Producer
Primary Consumer – eats producers

16. Food Chains Secondary Consumer – eats primary consumers Producer

17. Food Chains Tertiary Consumer – eats secondary consumers Producer
Primary Consumer
Secondary Consumer
Tertiary Consumer – eats secondary consumers

18. Food Chains
Tertiary
Consumer
Producer
Primary Consumer
Secondary Consumer
Decomposer - bacteria and fungi that break down dead organisms and recycle the material back into the environment

19. Food Chains Tertiary Consumer Producer Primary Consumer
Secondary Consumer
Decomposer

20. Food Webs Interconnected food chains in a community
Identify the following:
Producers
plants
Primary Consumers
grasshopper, mouse, rabbit, squirrel
Secondary Consumers
fox, mouse, frog, snake
Tertiary Consumers
owl, fox, snake
Herbivores
grasshopper, rabbit, squirrel
Carnivores
fox, owl, snake, frog
Omnivore
mouse
What element is missing?
decomposers

21. Ecological Pyramid
Shows the relative amounts of energy or matter contained at each trophic level
The Pyramid shows which level has the most energy and the highest number of organisms