1. Chapter 3 What is Ecology?
Prentice Hall
P.60-85

2. Chapter 3 What is Ecology ? SOL 9
The branch of biology that developed from natural history is called ecology.
Ecology is the study of interactions that take place between organisms and their environment.
Section 2.1 Summary – pages

3. The Biosphere
The biosphere is the portion of Earth that supports living things.
It extends from high in the atmosphere to the bottom of the oceans.

4. The nonliving environment: Abiotic factors
The nonliving parts of an organism’s environment are the abiotic factors.
Examples: air currents, temperature, moisture, light, and soil.
Prentice Hall introduces abiotic and biotic in Chapter 4 (4-2 p. 90)

5. The living environment: Biotic factors
A key consideration of ecology is that living organisms affect other living organisms
All the living organisms that inhabit an environment are called biotic factors.
All organisms depend on others directly or indirectly for food, shelter, reproduction or protection.

6. Levels of Organization
Ecologists study individual organisms, interactions among organisms of the same species, interactions among organisms of different species, as well as the effects of abiotic factors on interacting species.
Ecologists have organized the living world into levels
the Organism by itself (species),
Population- all members of one species in an area
Community- all populations in a given area
Ecosystem- community + the nonliving factors (ABIOTIC)
Biome –ecosystems with similar climate and similar
dominant communities
Biosphere – biotic + abiotic factors of the entire Earth

7. Levels of Organization

8. Observing – use of one or more of the senses to gather information
Ecological Methods
Observing – use of one or more of the senses to gather information
Experimenting –testing hypotheses either in the lab or in the field
Modeling – involves constructing a representation of an object, a system or a process that helps show relationships among data = an explanation supported by data
Modeling often consists of mathematical formulas

9. Ecological Methods Observation Experiment Model Building Sites
Field site
Experimental plots,
field sites, laboratory
Many sites for data
collecting
Measuring Tools
Tapes, compass,
Global Positioning
System, thermometer,
sensors
Aerial views, Global
Positioning System,
weather balloons
Magnifying Tools
Binoculars, microscope,
telescope
Satellite images
Written Record
Notes, automated data
storage
Automated data storage
Chemical Testing
Test kits
Large database,
multiple sensors
Computer/
Calculators
Mathematical analysis
and graphics, statistics
and graphics, statistics,
simulations

10. Ecological research
Ecologists obtain quantitative data by making measurements and carrying out controlled experiments in the field and in the laboratory.

11. Question 1 A. abiosis B. symbiosis C. ecology D. biology
The study of interactions that take place between organisms and their environment is __________.
A. abiosis
B. symbiosis
C. ecology
D. biology
Section 1 Check

12. The answer is C. Ecology is a branch of biology that developed from natural history.
Section 1 Check

13. Question 2 A. moisture B. soil C. earthworm D. light
Which of the following is a biotic factor?
A. moisture
B. soil
C. earthworm
D. light
Section 1 Check

14. The answer is C. Biotic factors are all the living organisms that inhabit an environment.
Section 1 Check

15. Question 3 A. biological community B. population C. ecosystem
A(n) __________ is a group of organisms, all of the same species, which interbreed and live in the same place at the same time.
A. biological community
B. population
C. ecosystem
D. habitat
Section 1 Check

16. The answer is B. Communities and ecosystems are comprised of more than one species. Habitat refers to the place an organism lives.
Section 1 Check

17. Question 4
Which type of organism consumes both plant and animal products?
A. herbivore
B. carnivore
C. predator
D. omnivore
Chapter Assessment

18. The answer is D. Humans are omnivores and eat a variety of foods that include both plant and animal materials. The figure shows recommended food servings for good health.
Chapter Assessment

19. Energy Flow All organisms need energy for life activities
This energy comes from their food.
Consumption of food is an energy transfer
Food Chains
Food Webs

20. The producers: Autotrophs
The ultimate source of the energy for life is the sun.
Plants use the sun’s energy to manufacture food in a process called photosynthesis.

21. Good Time to review Chemical Equations ( Reactants and Products)

22. Chemosynthesis – use chemical energy to produce food instead of light
Life Without Light

23. The producers: Autotrophs
An organism that uses light energy or energy stored in chemical compounds to make energy-rich compounds is a producer, or autotroph
Other organisms in the biosphere depend on autotrophs for nutrients and energy. These dependent organisms are called consumers or heterotrophs

24. The consumers: Heterotrophs
An organism that cannot make its own food and feeds on other organisms is called a heterotroph
A heterotroph that feeds only on plants is an herbivore.
Some heterotrophs eat other heterotrophs. Animals such as lions that kill and eat only other animals are carnivores.
Detritivores- eat dead plants and animals (detritus)
Ex: mites, earthworms, snails, crabs
Some organisms, such as bacteria and fungi, are decomposers. Decomposers break down the complex compounds of dead and decaying plants and animals into simpler molecules that can be more easily absorbed.

25. Producers: organisms that make their own food

26. Herbivore: animal that eats plants (Primary Consumer)

27. Carnivore: animal that eats other animals (Secondary consumer, Tertiary consumer,
Quaternary consumer etc)

29. Decomposer: an organism that feeds on
dead organic material

30. Detritivore (Scavenger): consumer that feeds on remains of dead organisms
Detritivores – dee-TRYT-uh-vawrz

31. Flow of Matter and Energy in Ecosystems
A food chain is a simple model that scientists use to show how matter and energy move through an ecosystem.
In a food chain, nutrients and energy move from autotrophs to heterotrophs and, eventually, to decomposers.
A food chain is drawn using arrows to indicate the direction in which energy is transferred from one organism to the next.
Most food chains consist of two, three, or four transfers.
The amount of energy remaining in the final transfer is only a portion of what was available at the first transfer.
A portion of the energy is given off as heat at each transfer.

32. Simple Food Chain

33. Trophic levels represent links in the chain
Each organism in a food chain represents a feeding step, or trophic level, in the passage of energy and materials
Primary Consumer (Herbivore)(first order heterotroph) is an organism that feeds on plants, such as a grasshopper.
Secondary Consumer (Carnivore) (A second order heterotroph) is an organism that feeds on a first order heterotroph.
A food chain represents only one possible route for the transfer of matter and energy through an ecosystem.

35. Food web
A food web, shows all the possible feeding relationships at each trophic level in a community.

36. Three different types of Ecological Pyramids:
An ecological pyramid
shows the amount of energy or matter in an ecosystem.
Shows relative amounts of energy or matter contained in each trophic level
The base of the ecological pyramid represents the autotrophs, or first trophic level. Higher trophic levels are layered on top of one another.
Three different types of Ecological Pyramids:
1. Energy
2. Biomass
3. Pyramid of Numbers

37. Energy pyramids The pyramid of energy illustrates that
the amount of available energy decreases at each succeeding trophic level.
the total energy transfer from one trophic level to the next is only about ten percent because
organisms fail to capture and eat all the food
energy available at the trophic level below them.
2. They use much of the energy for life processes
3. Some of the energy is released as heat

38. Pyramid of Energy
Section 2.2 Summary – pages

39. Pyramid of Biomass
A Pyramid of Biomass is the total weight of living matter at each trophic level.
1 kilogram of human tissue
10 kilograms of beef
100 kilograms of grain
Section 2.2 Summary – pages

40. Biomass Pyramid

41. Pyramids of Numbers
A pyramid of numbers shows that population sizes decrease at each higher trophic level.
Fox (1)
Birds (25)
Grasshoppers (250)
Grasses (3000)
Section 2.2 Summary – pages

42. Question 5 A. autotroph B. heterotroph C. decomposer D. herbivore
Which of the following is a producer?
Chloroplast
A. autotroph
Nucleus
Mitochondrion
B. heterotroph
Eyespot
C. decomposer
D. herbivore
Flagellum
Pellicle
Contractile vacuole
Section 2 Check

43. The answer is A. Organisms that make energy-rich compounds are producers, or autotrophs.
Chloroplast
Nucleus
Mitochondrion
Eyespot
Flagellum
Pellicle
Contractile vacuole
Section 2 Check

44. Question 6 A. autotrophs, autotrophs B. autotrophs, heterotrophs
In a food chain, nutrients and energy move from __________ to __________.
A. autotrophs, autotrophs
B. autotrophs, heterotrophs
C. heterotrophs, autotrophs
D. decomposers, autotrophs
Section 2 Check

45. The answer is B. The first level in all food chains is made up of producers.
berries → mice → black bear
Section 2 Check

46. Question 7 A. food pathway B. food chain C. food matrix D. food web
A model of all the possible feeding relationships at each trophic level in a community is a(n) __________.
A. food pathway
B. food chain
C. food matrix
D. food web
Section 2 Check

47. The answer is D. A food web is a more realistic model than a food chain, because most organisms depend on more than one other species for food.
Section 2 Check

48. Question 8
Which of the following models best illustrates heat released at each trophic level of an ecosystem?
A. food chain
B. food web
C. pyramid of energy
D. pyramid of biomass
Chapter Assessment

49. The answer is C. The pyramid of energy shows energy available
The answer is C. The pyramid of energy shows energy available. Organisms at each trophic level use some energy in food for metabolism and some is given off as heat. The total amount of energy remains the same in accordance with the law of conservation of energy.
Pyramid of Energy
Heat
0.1% Consumers
Heat
1% Consumers
10% Consumers
Heat
100% Producers
Heat
Parasites, scavengers, and decomposers feed at each level.
Chapter Assessment

50. Question 9
Compare the amount of energy available in the biosphere to the amount of matter here.
Chapter Assessment

51. ANSWER
Both energy and matter are conserved: they may be transformed, but are not destroyed. However, sunlight is the primary source of all the energy utilized and transferred in the biosphere. It is always being replenished by the sun.
In contrast, there is a finite amount of matter in the biosphere, which is cycled and not replenished.
Chapter Assessment

52. Cycles in Nature
Matter, in the form of nutrients, moves from one organism to another and from one part of the biosphere to another through biogeochemical cycles,
Matter is cycled and is not replenished like the energy from sunlight. There is a finite amount of matter.

53. Major Processes in Water Cycle
1. Precipitation- water vapor condensing and falling from the atmosphere
2. Evaporation – liquid water changing to a gas
3. Transpiration- water evaporating from plants
The cycling of water is driven by heat from the sun

54. The Water Cycle Condensation Precipitation Evaporation Transpiration
Runoff
Seepage
Root
Uptake

55. The Water Cycle
In the water cycle, water is constantly moving between the atmosphere and Earth.
Condensation
Evaporation
Precipitation
Transpiration
Runoff
Evaporation
Oceans
Groundwater
Section 2.2 Summary – pages

56. Water Cycle

57. Carbon Cycle Carbon and Oxygen combine to form Carbon Dioxide.
Plants use Carbon Dioxide during photosynthesis to produce sugars.
Plants use sugars for plant growth & respiration
Herbivores eat plants, and incorporate molecules into their structures.
Respiration breaks down sugars releasing CO2 and water back into the atmosphere.

58. Carbon Cycle Major Processes are: 1. Photosynthesis:
6 CO H2O  C6H12O6 + 6 O2.
Carbon Dioxide Water Glucose Oxygen
2. Respiration:
C6H12O6 + 6 O2  6 CO2 + 6 H2O
Glucose Oxygen Carbon Dioxide Water

59. Carbon Cycle

60. Nitrogen Cycle Relies heavily on bacteria
Atmosphere major reservoir-78% N2
Nitrogen found in proteins and DNA, RNA
Plants need nitrogen in the form of nitrate ( NO3)
Animals get nitrogen from proteins in their food

61. Bacteria of the Nitrogen Cycle
1. Nitrogen-fixing bacteria -convert N2 in air to nitrates that plants can absorb and use
Symbiotic with legumes-found in nodules in roots of peas, beans, and clover
2. Bacteria of Decay - Decomposers- convert
nitrogenous wastes into ammonia (NH3)
3. Nitrifying bacteria – convert ammonia to nitrates
Denitrifying bacteria – break down nitrogen compounds into free nitrogen which returns to the atmosphere

62. The nitrogen cycle
In the nitrogen cycle, nitrogen is converted from a gas to compounds important for life and back to a gas.
N2 in Atmosphere
NO3 & NO2
NH3

63. Nitrogen Cycle

64. Phosphorus Cycle Main abiotic reservoir for phosphorus is rock
Weathering of rock adds phosphorus to soil
Plants absorb phosphates from soil and build organic compounds (ATP, DNA, bones)
Animals eat plants –incorporate phosphates in to animal compounds
Is not cycled in the atmosphere!

65. Phosphorus Cycle

66. Nutrient Limitation
Primary productivity = rate at which organic matter is created by producers
Limiting nutrient – a needed nutrient is in short supply- will affect growth and reproduction of organisms
Open Oceans – nutrient poor
Sea Water contains % Nitrogen (1/10,000 of amount usually found in soil)
Algal bloom – sudden increase in limiting factor causes sudden large increase in population of algae

67. Chlorella Algae

68. Question 10 Which of the following does not cycle into the atmosphere?
A. phosphorus
B. nitrogen
C. carbon
D. water
Chapter Assessment

69. The answer is A. Phosphorus moves between the living and nonliving parts of the environment, but does not enter the atmosphere as a gas.
Chapter Assessment

70. Question 11
How does water on Earth's surface get back into the atmosphere?
Condensation
Evaporation
Precipitation
Transpiration
Runoff
Evaporation
Oceans
Groundwater
Chapter Assessment

71. ANSWER
The processes of evaporation of water in lakes and oceans and transpiration by plants both put water vapor into the air.
Condensation
Evaporation
Precipitation
Transpiration
Runoff
Evaporation
Oceans
Groundwater
Chapter Assessment