1. Chapter 3
The Biosphere

2. I. Ecology
A. Study of the interactions among organisms & between organisms and their physical environment
B. Ecological Levels of Organization
1. Organism =
One individual
One group of species in same place and time
2. Population =
3. Community =
Two or more species (populations) that interact
Communities interacting with abiotic factors
4. Ecosystem =

3. pertains area where living organisms occur (land, water, air)
5. Biome =
Group of ecosystems
pertains area where living organisms occur (land, water, air)
6. Biosphere =
Biosphere
Page 64-65
Biome
Ecosystem
Community
Population
Individual

4. C. Biotic – any living or once living part of the environment
Examples: frogs, leaves, bacteria, mushrooms, dead leaves
D. Abiotic – any non-living part of the environment
Examples: air, water, rocks, dirt, sunlight, wind
Abiotic factors can affect biotic factors and vice versa
How?
Think about a drought how does it affect biotic organisms?
Think about biotic organisms near a watering hole?
E. Biotic and abiotic factors determine the survival and growth of an organism and productivity of the ecosystem

5. II. Energy Flow
A. Producers =
(autotrophs) produce their own food
Photoautotrophs = use sunlight to make their own food by photosynthesis
Examples: Plants, phytoplankton
2. Chemoautotrophs – use inorganic chemicals to make their food by chemosynthesis Examples: bacteria in deep-sea volcanic vents, hot springs
(heterotrophs) rely on other organisms for their food
B. Consumers =
1. Herbivores, Carnivores, Omnivores, Detritovores (feed on detritus – plant and animal remains), Decomposers (break down dead organic matter that produce detritus)

6. III. Feeding Relationships
A. Trophic Level =
Each step in a food chain/web
1. Producers are 1st, consumers 2nd, 3rd etc.
One way flow of energy from producers to consumers
B. Food Chain =
Page 73
Small Fish
Zooplankton
Squid
Shark
Algae
1. Eventually end up with detritivores & decomposers

7. C. Food Web
1. Shows complex interactions of all possible feeding relationships
2. More realistic
3. Many food chains connected
Page 75

8. D. Disturbance in a Food Web
1. Effects can be dramatic
Lets think:
What do you think would happen if there was an oil spill that caused a decline in bacteria and fungi that break down detritus?
How would that effect the populations of crayfish? Shrimp? Worms? Would their numbers decline?
If so, would that change the pig frogs feeding behavior? Would the pig frogs feeding behavior effect other species?

9. IV. Ecological Pyramids
A. Energy Pyramid (Page 77)
1. Shows the relative amount of energy available at each trophic level
0.1% Third-level consumers
2. Only 10% is transferred to the next level because some is lost to heat and energy is used for life processes.
1% Second-level consumers
10% First-level consumers
100% Producers

10. 1. The total amount of living tissue within a given trophic level
B. Biomass Pyramid
1. The total amount of living tissue within a given trophic level
2. represents the amount of potential food available for each trophic level
50 grams of human tissue
500 grams of chicken
5000 grams of grain

11. C. Pyramid of Numbers (Page 78)
1. Shows the relative number of individual organisms at each trophic level
2. Decreases at each higher trophic level
3. Not true for tree

12. V. Cycles of Matter
A. Biogeochemical Cycles
Matter is recycled within and between ecosystems which are powered by the flow of energy
Involves:
Biological Processes, Geological Processes, and Chemical Processes.
Human Activity can also play an important role

13. B. Water Cycle
Water moves between the ocean, atmosphere and land.
Precipitation, run-off, seepage, evaporation/transpiration, condensation (clouds)  precipitation
3. Transpiration = water evaporating from plants leaves to atmosphere
Page 81

14. C. Nutrient Cycles:
1. Every organism needs nutrients to build tissues and carry out life functions.
2. Nutrients pass through organisms and the environment through biogeochemical cycles.
D. Carbon Cycle
1. Carbon moves in biosphere by: photosynthesis, respiration, decomposition, volcanoes, coal/fossil fuels, mining
2. Carbon is a key ingredient of living tissue

15. Carbon Cycle Page 83 CO2 in Atmosphere CO2 in Ocean Carbonate Rocks
Photosynthesis
Volcanic activity
feeding
Respiration
Erosion
Human activity
Respiration
Decomposition
CO2 in Ocean
Uplift
Carbon is found in several large reservoirs in the biosphere. In the atmosphere, it is found as carbon dioxide gas; in the oceans as dissolved carbon dioxide; on land in organisms, rocks, and soil; and underground as coal, petroleum, and calcium carbonate rock. 
Deposition
Photosynthesis
feeding
Fossil fuel
Page 83
Deposition
Carbonate Rocks

16. Nitrogen Cycle Page 84 NH3 N2 in Atmosphere NO3 and NO2
Synthetic fertilizer manufacturer
Atmospheric nitrogen fixation
Denitrification
Uptake by producers
Reuse by consumers
Uptake by producers
Reuse by consumers
Decomposition, excretion
Decomposition, excretion
Bacterial nitrogen fixation
The atmosphere is the main reservoir of nitrogen in the biosphere. Nitrogen also cycles through the soil and through the tissues of living organisms. 
NO3 and NO2
NH3
Page 84

17. E. Nitrogen Cycle
1. All organisms require nitrogen to make proteins and DNA/RNA
2. Only certain bacteria can use Nitrogen gas as is
3. Nitrogen Fixation = bacteria change N2 into useable form (ammonia NH3)
4. Such bacteria live in soil & on roots of plants called legumes
5. Other soil bacteria convert nitrates (NO2- & NO3-) into N2 gas  called denitrification = releases nitrogen into the atmosphere

18. F. Phosphorus Cycle
1. Essential to living organisms for DNA/RNA
2. Not common in atmosphere
3. Rock wears down  phosphorus in soil & can wash into sea  plants get phosphorus from soil and eventually die  animals eat plants and die  phosphorus is back in soil

19. Phosphorus Cycle
Organic phosphate moves through the food web and to the rest of the ecosystem.
Organisms
Phosphorus in the biosphere cycles among the land, ocean sediments, and living organisms.
Land
Ocean
Page 85
Sediments

20. G. Nutrient Limitation
1. Limiting Nutrient  a nutrient whose supply limits productivity
a. May be scarce or cycles very slowly
b. If any nutrient is in short supply, the whole system slows down or stops altogether
Example: A large input of a limiting nutrient to aquatic ecosystems — such as runoff from heavily fertilized fields — the result is often an immediate increase in the amount of algae and other producers = Algal Bloom  disrupts the equilibrium of an ecosystem.

22. 3-1
The combined portions of the planet in which life exists, including land, water, and the atmosphere, form the
A. biosphere.
B. community.
C. species.
D. ecosystem.

23. 3-1
A group of organisms that can breed and produce fertile offspring is known as a(an)
A. ecosystem.
B. species.
C. biome.
D. community.

24. 3-1 Compared to a community, an ecosystem includes
A. the nonliving, physical environment as well as the community.
B. only the physical environment of an area without the organisms.
C. the entire biome but not the biosphere.
D. only one of the populations within the community.

25. 3-1
An ecological method that uses mathematical formulas based on data collected is
A. observing.
B. experimenting.
C. modeling.
D. hypothesizing.

26. 3-1
An ecologist marks out an area in a specific ecosystem and proceeds to identify the number of insect species in the area. This is an example of ecological
A. experimentation.
B. observation.
C. modeling.
D. inference.

27. 3–2 The main source of energy for life on Earth is
A. organic chemical compounds.
B. inorganic chemical compounds.
C. sunlight.
D. producers.

28. 3–2
Organisms that feed on plant and animal remains and other dead matter are
A. detritivores.
B. carnivores.
C. herbivores.
D. autotrophs.

29. 3–2 How does a food web differ from a food chain?
A. A food web contains a single series of energy transfers.
B. A food web links many food chains toget
C. A food web has only one trophic level.
D. A food web shows how energy passes from producer to consumer.

30. 3–2
In a biomass pyramid, the base of the pyramid represents the mass of
A. heterotrophs.
B. primary consumers.
C. producers.
D. top level carnivores.

31. 3–2
The amount of energy represented in each trophic level of consumers in an energy pyramid is about
A. 10% of the level below it.
B. 90% of the level below it.
C. 10% more than the level below it.
D. 90% more than the level below it.

32. 3–3 Transpiration is part of the A. water cycle. B. carbon cycle.
C. nitrogen cycle.
D. phosphorus cycle.

33. 3–3 Carbon is found in the atmosphere in the form of A. carbohydrates.
B. carbon dioxide.
C. calcium carbonate.
D. ammonia.

34. 3–3
Biologists describe nutrients as moving through cycles because the substances
A. start as simple organic forms that plants need.
B. provide “building blocks” and energy that organisms need.
C. are passed between organisms and the environment and then back to organisms.
D. are needed by organisms to carry out life processes.

35. 3–3
The only organisms that can convert nitrogen in the atmosphere into a form useful to living things are nitrogen-fixing
A. plants.
B. bacteria.
C. detritivores.
D. animals.

36. 3–3
When an aquatic ecosystem receives a large input of a limiting nutrient, the result is
A. runoff.
B. algal death.
C. algal bloom.
D. less primary productivity.