1. Organisms and Their Relationships
Chapter 2, Section 1

2. Ecology
Ecology is the study of how living organisms interact with other living things and how they interact with their environment.
Ecologists study organisms, their adaptations, and environmental factors

3. The Biosphere
The portion of Earth that supports life is called the biosphere
Biosphere includes ONLY the part of the Earth that includes life; it extends into the atmosphere and below the ocean’s surface

4. The Biosphere
Biotic factors
Abiotic factors
The living things in an organism’s environment are the biotic factors
Examples?
Nonliving things in an organism’s environment are abiotic factors.
Examples?
Organisms depend on these for survival
Organisms are adapted to abiotic factors in their environment

5. Levels of Organization
Increase in complexity as #s and interactions between organisms also increases
From smallest to largest….
Organism (individual living thing)
Population (group of organisms in same species; can interbreed)
Biological community (all populations in the same place; only living things)
Ecosystem (all biotic and abiotic factors in a community)
Biome (group of ecosystems with similar climates & communities)
Biosphere

6. Ecosystem Interactions
A community increases its chance for survival when it shares available resources by using them in different ways
Ex- birds in the same tree but different levels
A habitat is the area where an organism lives
Niches are the role or position an organism has in the environment
How it gets food, shelter, and reproduces

8. Community Interactions
Competition- occurs when 1 or more organisms use the same resource at the same time
Usually strong survive and weak die
Predation- one organism pursues & consumes another organism for food

9. Symbiosis
Is the relationship that exists when 2 or more species live together
3 kinds
Mutualism- both benefit
Commensalism- one benefits & the other is not helped or harmed
Parasitism- one benefits & the other is harmed

10. Flow of Energy in an Ecosystem
Section 2, Ch 2

11. Energy in an Ecosystem Models of Energy Flow Autotrophs Heterotrophs
Food chains
Food webs
Ecological pyramids

12. Energy in an Ecosystem
Autotrophs collect energy from the sun or inorganic substances to produce food
Are the foundation of ecosystems because they make energy available for all other organisms
Heterotrophs consume other organisms for energy
Are predators; make up remaining levels
Omnivores eat plants and animals
Detritivores eat fragments of dead matter
**As energy is passed from one level to another, 10% is the total that is passed on! SO- 90% is lost each time (heat, metabolism, energy expended to catch food)

13. Models of Energy Flow Each step is called a trophic level
Food chains show how energy flows through an ecosystem

14. Models of Energy Flow
Food webs show interconnected food chains; shows energy flow through a group of organisms

15. Section 2
Principles of Ecology

16. Ecological pyramids show energy flow through an ecosystem
Shows relative amount or energy, number of organisms at each level or biomass

17. Cycling of Matter
Section 3, Ch 2

18. Objectives
I can determine how nutrients, such as carbon, oxygen, water, and phosphorus, move through the environment.
I can identify the nutrients that are important to living organisms.
I can find similarities between the biogeochemical cycles on earth.

19. Cycles in the Biosphere
Natural processes cycle matter through the biosphere because it is not created or destroyed
The exchange of matter through the biosphere is called a biogeochemical cycle
Anything that takes up space and has mass is matter
Nutrients are chemical substances that organisms must get from the environment to live and perform life processes
Producer  consumer

20. The Cycles!! The water cycle The carbon and oxygen cycle
The nitrogen cycle
The phosphorus cycle

21. Section 3
Principles of Ecology

22. The water (H2O) cycle

23. The water (H2O) cycle
Water constantly evaporates, condenses, then falls back to the atmosphere
About 90% comes from the oceans, lakes & rivers; 10% comes from plants
Runoff flows into streams, lakes, etc.

24. The carbon (C) and oxygen cycle (O)

25. Section 3
Principles of Ecology

26. The carbon (C) and oxygen cycle (O)
Both are essential for life; CO2 & simple sugars
Carbon
Long-term: Organic matter converted to peat, coal, oil, or gas deposits (carbon)
Short-term: Burning fossil fuels (carbon)

27. The nitrogen cycle (N)
Pg 48

28. Section 3
Principles of Ecology

29. The nitrogen cycle (N)
N is found in proteins; largest concentration is in atmosphere but it cannot be used directly in this form
Nitrogen fixation is the process of capturing & converting N to a useable form

30. The phosphorus cycle (P)
Pg 49

31. Section 3
Principles of Ecology

32. The phosphorus cycle (P)
Essential for growth & development of organisms
2 cycles:
short-term: P becomes part of a solution; cycles from soil  producers  consumers; decomposers return P to soil when organisms die or produce waste
long-term: weathering or erosion of rocks adds P to the cycle
P limits the growth of producers