1. DO NOW
Answer the following: What is Ecology?

2. 3.1 - Studying Our Living Planet
Ecology is the scientific study of interactions among organisms and between organisms and their environment.

3. Chapter 3
The Biosphere
Biology CP
P. Smith

4. Biosphere Earth’s organisms live in the biosphere.
The biosphere consists of the parts of the planet in which all life exists.
Ecologists may study different levels of ecological organization:
Individual organism
An assemblage of individuals that belong to the same species and live in the same area is called a population.
An assemblage of different populations that live together in an area is referred to as a community.

6. Ecosystem
An ecosystem includes all the organisms that live in a particular place, together with their physical environment.
A group of ecosystems that have similar climates and organisms is called a biome.

7. Biomes
A group of ecosystems that have similar climates and organisms is called a biome.
Examples
Tropical Rain Forest
Desert
Temperate Forest ( we live here)

8. Biotic and Abiotic Factors
Ecosystems include biotic and abiotic factors.
A biotic factor is any living part of an environment.
An abiotic factor is any nonliving part of an environment.

9. Ecological Methods
Ecologists use three basic methods of research: observation, experimentation, and modeling:
Observation often leads to questions and hypotheses.
Experiments can be used to test hypotheses.
Modeling helps ecologists understand complex processes.

10. 3.2 Energy, Producers & Consumers
Primary Producers
Sunlight is the main energy source for life on Earth.
Organisms that can capture energy from sunlight or chemicals and use that energy to produce food are called autotrophs, or primary producers.

11. Primary Producers = Autotrophs
The process in which autotrophs capture light energy and use it to convert carbon dioxide and water into oxygen and sugars is called photosynthesis.
The process in which autotrophs use chemical energy to produce carbohydrates is called chemosynthesis.

12. Photoautotrophs
Without autotrophs, there would be no life on this planet
Ex. Plants and Algae

13. Autotrophs Chemotrophs
Autotrophs that get their energy from inorganic substances, such as salt
Live deep down in the ocean where there is no sunlight
Ex. Bacteria and Deep Sea Worms

14. Consumers = Heterotrophs
Organisms that do not make their own food
Another term for Heterotroph is consumer because they consume other organisms in order to live
Ex. Rabbits, Deer, Mushrooms

15. Heterotrophs
Deer
Rabbits
Mushrooms

16. Heterotrophs = Consumers
Herbivores – eat ONLY plants
Ex. – Cows, Elephants, Giraffes

17. Heterotrophs = Consumers
Carnivores – eat ONLY meat
Ex. – Lions, Tigers, Sharks

18. Heterotrophs = Consumers
Omnivores – eat BOTH plants and animals
Ex. – Bears and Humans
Kyle Smith

19. Heterotrophs = Consumers
Detritivores - feed on the tissue (detritus) of dead organisms (plant or animal)
Shrimp, earthworms, dust mites

20. Heterotrophs = Consumers
Decomposers – absorb any dead material and break it down into simple nutrients or fertilizers
Ex. – Bacteria and Mushrooms

21. Heterotrophs = Consumers
Scavengers– Consumes the carcasses of dead animals but does not typically kill them itself.
Ex. – Vultures & Crows

22. Energy Flow in Ecosystems (Transfer of Energy)
When a zebra eats the grass, it does not obtain all of the energy the grass has (much of it is not eaten)
When a lion eats a zebra, it does not get all of the energy from the zebra (much of it is lost as heat)

23. Transfer of Energy
The two (2) previous examples of energy transfer show that no organism EVER receives all of the energy from the organism they just ate
Only 10% of the energy from one trophic level is transferred to the next – this is called the 10% law

24. Trophic Levels
Energy moves from one organisms to another when it is eaten
Each step in this transfer of energy is know as a trophic level
The main trophic levels are producers, consumers, and decomposers

25. Food Chains
The energy flow from one trophic level to the other is know as a food chain
A food chain is simple and direct
It involves one organism at each trophic level
Primary Consumers – eat autotrophs (producers)
Secondary Consumers – eat the primary consumers
Tertiary Consumers – eat the secondary consumers
Decomposers – bacteria and fungi that break down dead organisms and recycle the material back into the environment

26. Food Chain

27. Food Web Most organisms eat more the JUST one organism
When more organism are involved it is know as a FOOD WEB
Food webs are more complex and involve lots of organisms

28. Food Web

29. Food Web
Notice that the direction the arrow points  the arrow points in the direction of the energy transfer, NOT “what ate what”

30. Food Web

31. Biomass
The total mass of the organic matter at each trophic level is called biomass
Biomass is just another term for potential energy – energy that is to be eaten and used.
The transfer of energy from one level to another is very inefficient (10% Law)

32. Biomass

33. Ecological Pyramid
An ecological pyramid shows the relationship between consumers and producers at different trophic levels in an ecosystem
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

34. Ecological Pyramid Which level has the most energy?
Which level has the most organisms?
Which level has the least organisms?
Which level has the least energy?

35. Ecological Pyramid

36. Ecological Pyramid