1. Chapter 3: The Biosphere
Ecology
Chapter 3: The Biosphere

2. What Is Ecology?
Ecology- is the study of the interactions among organisms and between the organisms and the environments in which they live.
(eco means “house”) .
Biotic factors – all living things
Ex. Types of plants, animals, bacteria, fungi, etc.
Abiotic factors – all non-living things
Ex. Climate, temperature, amount of rainfall, humidity, light, wind, soil type, nutrients available, etc.

3. Ecological Levels of Organization
Smallest Largest
Individual  Population  Community  Ecosystem  Biome  Biosphere
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4. Levels of Organization Summary
Species-or individual
Population- all of one species
Communities-all populations
Ecosystems- all populations + environment
Biome- large stable ecosystems
Biosphere- Part of Earth where life exists (all biomes)

5. Species / Individual
A group of similar looking organisms that can breed with one another to produce fertile offspring.

6. Populations
Groups of individuals within the same species that live in the same area (habitat).

7. Communities
All Populations of various species that live together in a defined area.

8. Ecosystems
all members of a community & the physical environment they live in
What abiotic factors are present?
What biotic factors are present?
Habitat: place where an organism lives

9. Biome
large, stable groups of ecosystems that share the same biotic and abiotic factors
Tropical Rainforest
Highlighted Regions

10. Biosphere
The part of Earth where life exists.

11. What term is used to refer to each of the following?
_________________1. Lake Houston (location)
_________________2. Mississippi river and all of the forms of life that are sustained by it
_________________3. A flock of ducks
_________________4. The Sahara desert
_________________5. All livable areas on Earth
_________________6. All the deer, ducks, shore birds, fish and rabbits in an area
Habitat
Ecosystem
Population/species
Biome
Biosphere
Community

12. Practice:
Species / Individual
Population
Community
Ecosystem

13. The flow of energy through an ecosystem begins with the SUN, and is passed on through various organisms
Sunlight  Producers  Consumers  Decomposers

14. Sunlight  Producers  Consumers  Decomposers
Producers autotrophic organisms that are able to make own food from a inorganic substances.
Ex. Plants, algae (phytoplankton-microscopic marine plant life)

15. Consumers:
Sunlight  Producers  Consumers  Decomposers
Consumers: heterotrophic organisms that get energy by eating producers and other consumers. (ex. Deer, hawk, bear)

16. Consumers: Herbivores: eat producers (plants)
Sunlight  Producers  Consumers  Decomposers
Herbivores: eat producers (plants)
ex. Deer, grasshopper, cow
Carnivores: eat other consumers (meat)
ex. Frog, wolf, hawk
Omnivores: eat producers and consumers
ex. Grizzly bear, humans
Detritovore: organic wastes and dead bodies of plants and animals…. ex. mites, ` earthworms, snails, crabs, vultures

17. Consumers: Level of Consumers: Herbivore Carnivore
Sunlight  Producers  Consumers  Decomposers
Level of Consumers:
Primary consumer Secondary consumer3rd, 4th …level consumer
________________ __________________
_______________________ can be 1st,2nd or higher level consumer
Herbivore
Carnivore
Omnivore & decomposers

18. Decomposers: Bacteria and Fungi
Sunlight  Producers  Consumers  Decomposers
Decomposers:
Obtain energy from eating the remains of other organisms (recyclers) Ex.
Two Principle Decomposers:
Bacteria and Fungi
Worms
Bacteria
Fungi
Termites
Earthworms and termites (detritivores) also aid in the breakdown of organic matter, which replenishes nutrients to the soil.

19. Feeding Relationships
1st
2nd
3rd
4th
5th
Decomposers
Each step in the food chain or web is called a trophic level, or a feeding relationship between organisms.
What is always found at the second trophic level?

20. Food Chains
Food Chain a series of steps in which organisms transfer energy by eating and being eaten.
Energy flows to
Energy flows to
Energy flows to
The arrows show the flow of energy and matter as one organism is eaten by another.

21. Trophic Levels 5th 4th consumers Top Carnivores 4th
3rd consumers Carnivores
Secondary consumers Carnivores
3rd
2nd
Primary consumers Herbivores
1st
Producers

22. When studying the overall health of an ecosystem, we study food webs.
Food Web: links all the food chains in an ecosystem together.
Any change in a population or trophic level of a food chain can seriously alter all other organisms of the food web!
A healthy ecosystem has a large diversity of life because of the availability of alternative food sources.
When studying the overall health of an ecosystem, we study food webs.

23. Practice:
What would happen to this food web is the plants were removed? ___________________________
Which organism is most vulnerable to changes in populations?______________________________
What happens to the owl population if the foxes we killed off by humans?________________________
All populations would die out
The frog has only one food source
The owl pop. would increase

24. We can show what goes on with the help of a Food Web

25. What would happen if a disease killed off many of the hawks?

26. There will be nothing to eat the snakes, so their numbers will increase.

27. All the frogs get eaten

28. No frogs.
More crickets

29. Most of the cattail gets eaten by the crickets

30. Now the crickets don’t have enough food so their numbers go down

31. ..and so on. Numbers of each species have an effect on the numbers of the other species in the web.

32. ECOLOGICAL PYRAMIDS
Ecological Pyramids: show relative amounts of energy or matter contained within each trophic level in a food chain or food web.

34. Energy Pyramid:
Kcal= kilocalorie
A pyramid of energy illustrate the loss of usable energy at each feeding level.
Of all the energy consumed by one level, 90% of the energy is used in the individual’s metabolism. (and lost as heat)
Only about 10% of the energy available within one trophic level is transferred to organisms at the next trophic level. (locked in body tissues)
1 Kcal: Humans
10 Kcal: tuna
100 Kcal: zooplankton
1000 Kcal: plankton
Why do most food chains have no more than 4 or 5 trophic levels?
There is very little energy transferred to support higher trophic levels

35. Pyramid of Numbers
show how many individuals are required to support the next level of feeding.
Why must there be so many more individuals at lower trophic levels?
Higher trophic levels have to eat more to get the same amount of energy due to the 10% rule.

36. Water and Nutrient Cycles
Energy cannot be recycled or used again.
However, nutrients/elements in an ecosystem can be recycled.
When an animal dies, its matter does not disappear; rather, it decomposes and gets used by another organism (through biogeochemical cycles).
This occurs through the water cycle, carbon cycle, nitrogen cycle, and phosphorous cycle.

37. The Water Cycle
1. According to the diagram, where does evaporation take place from?
From Lakes and oceans
2. When water evaporates from the surface of the Earth, what process creates clouds?
Condensation
3. Water falls to the earth in a process called
precipitation.
What are the 4 types of precipitation?
Rain, snow, sleet, hail

38. The Water Cycle
4. Plants return excess water to the atmosphere by evaporating water from its leaves in a process called:
Transpiration
5. Animals return water by
urination, perspiration, and respiration.
6. Other than plant and animal usage, what are other destinations for the precipitation that falls to the Earth?
It can become surface runoff or groundwater
7. What will ultimately happen to the ground water and surface water runoff?
It flows back to lakes and rivers to be evaporated again.

39. The Carbon Cycle
Name and discuss the process that removes carbon dioxide from the atmosphere?
In photosynthesis, producers remove CO2 gas from the atmosphere to make organic molecules (sugars).

40. The Carbon Cycle
2. Name and discuss the processes in which carbon dioxide is returned to the atmosphere?
Cellular respiration Animals burn the food they eat releasing CO2 gas as a waste product.
Combustion: Burning Fossil Fuels. When they are burned, CO2 gas is returned to the atmosphere and increases the amount of CO2 gas in the air.

41. The Carbon Cycle
3. How is carbon dioxide related to the green house affect?
Carbon dioxide, methane, and other gases trap heat energy and maintain Earth’s Temperature range.

42. The Carbon Cycle
4. It is thought that global warming is caused by adding carbon dioxide to the atmosphere.
What activities (by human or natural causes) are thought to speed up global warming?
Burning fossil, cutting down forest, and polluting oceans (most photosynthesis occurs in oceans)

43. The Nitrogen Cycle
1. Bacteria living in the roots of the plant help the plant by
convert nitrogen gas to ammonia
2. Bacteria living in the soil help plants by
converting ammonia and nitrogen gas into nitrates and nitrites.
3. What process transforms nitrogen into usable forms that plants can use?
Nitrogen fixation
4. What do plants use these nitrates and nitrites to make?
Proteins
Air is 78% nitrogen
Nitrogen is one of the elements found in plant fertilizers
Protein contains nitrogen

44. The Nitrogen Cycle
5. Where do animals ultimately get their proteins from?
Plants
6. How has farming affected the nitrogen cycle?
Fertilizers add nitrogen compounds to soil for plants to use.
7. How has industry affected the nitrogen cycle?
Burning fossil fuels release nitrogen compounds that fall to the earth as acid rain.
Air is 78% nitrogen
Nitrogen is one of the elements found in plant fertilizers
Protein contains nitrogen