Ecosystems Structure:
Key Concept: Ecology is the study of relationships among organisms and their environment.
Levels of organization
1. Label this diagram
with the correct level
2. Fill in the table below
Level
Description
Example
Organism
Population
Community
Ecosystem
Biome
Main Idea: An ecosystem includes both biotic and Abiotic factors.
Use the box below to complete the following sentences.
Abiotic
Living
Plants
3.
4.
5.
6.
7.
8.
9.
Animals
Moisture
Temperature
Biotic
Nonliving
Wind
All ecosystems are made up of _____ and ______components
__________factors are living things, such as ______________ or ____________
_________ factors are nonliving things such as, __________, ___________, or ___________
What is the difference between a biotic and an Abiotic factor?
List two (2) Abiotic factors ____________________________________________
List two (2) Biotic factors______________________________________________
Label the biotic and Abiotic parts of the ecosystem in the picture below
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Key Concept: Life in an ecosystem requires a source of energy.
Main Idea: Producers provide energy for other organisms in ecosystems
Complete the following sentence with the correct term
Autotrophs
Consumers
eating
heterotrophs
nonliving
producers
10. ___________ are organisms that get their energy from the _________________ resources, meaning they
make their own food. These organisms are also called ______________.
11. __________are organisms that get their energy by ______________ other organism. These organisms are
also called______________.
12. Why do all ecosystems depend on the producers?
13. Why is the sun important to both producers and consumers?
14. What is the difference between and consumer and a producer?
Key Concept: Food chains and food webs model the flow of energy in an ecosystem
Main Idea: a food chain is a model that show the sequence of feeding relationships
Complete the following sentence with the correct term
Carnivore
Decomposer
Detritivore
Herbivore
Omnivore
Primary Consumer
Secondary Consumer
Tertiary Consumer
Trophic Levels
15. I eat only plants. I am a(n) _____________________.
16. I eat only other animals. I am a(n) _____________________.
17. I eat both plants and animals. . I am a(n) _____________________.
18. I eat dead organic matter. . I am a(n) _____________________.
19. I break down organisms matter into simpler compounds. . I am a(n) _____________________.
20. I am the first consumer, above the producer level. . I am a(n) _____________________.
21. I am a carnivore that eats herbivores. . I am a(n) _____________________.
22. I am a carnivore that eats other carnivores. . I am a(n) _____________________.
23. The levels of nourishment in the food chain are called______________________.
Main Idea: Food webs shows complex feeding relationships
24. How is a food web different from a food chain?
25. What happens to the energy at each link in the web?
26. What type of organism is the base of the food web?
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A Food Web Shows:
Types of Consumers:
1. ________________________________________________
2. ________________________________________________
3. ________________________________________________
4. _________________________________________________
Trophic Levels
Producer
__________________
__________________
Primary Consumers
__________________
__________________
__________________
_________________
_
Secondary Consumers
__________________
__________________
_________________
_
Tertiary Consumer
__________________
Key Concept: Pyramids model the distribution of energy and matter in an ecosystem
Main idea: Energy pyramids show the distribution of energy among trophic levels.
Complete the following sentence with the correct term
Heat
Biomass
Waste
27. The measure of the total dry mass of organism in a given area is called _______________.
28. When a consumer incorporates the biomass of a producer into it’s biomass, a large amount of energy is
lost as _______________ and ______________________.
29. Label the four tiers of the energy pyramid with the correct trophic levels.
a. Assume you have 50 hawks, how many of each of
the following would you have? (Grass, Mice, Snakes)
b. Label the pyramid with the numbers and species
Main Idea: Other pyramid models illustrate an ecosystem’s
biomass and distribution of organisms.
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30. Fill in the table below
Model
Description
Energy Pyramid
Biomass Pyramid
Pyramid of numbers
31. What is biomass?
32. Describe how the energy flows from one level to the next?
ECOLOGICAL SUCCESSION
Key Concept: Ecological succession is a process of change in the species that make up a community
Main Idea: Succession occurs following a disturbance in an ecosystem.
33. What is ecological succession?
_____________________________________________________________________________________
_____________________________________________________________________________________
34. Fill in the chart below with a description and simple sketch of the main steps of primary succession.
_______________
_______________
_______________
_______________
_______________
_______________
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_______________
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_______________
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_______________
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_______________
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_______________
_______________
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_______________
_______________
35. Fill in the chart below with a description and simple sketch of the main steps of secondary succession.
_______________
_______________
_______________
_______________
_______________
_______________
_______________
_______________
_______________
_______________
_______________
_______________
_______________
_______________
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_______________
36. What is the main difference between primary and secondary succession?
_____________________________________________________________________________________
37. What are pioneer species?
_____________________________________________________________________________________
a) Why are pioneer species so important in primary succession?
____________________________________________________________________________
____________________________________________________________________________
b) Give an example of a pioneer species _____________________________________________
38. Why might succession be considered a never-ending process?
_____________________________________________________________________________________
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Population Growth Patterns
Key Concept: Populations grow in predictable patterns
Main Idea: changes in population size are determined by birth, death, immigration and emigration.
Complete the following sentence with the correct term
Birth
Death
Immigration
Emigration
39. When resources are abundant in an area, individuals may move into the population in that area. This
movement of individuals into a population from a different population is called ______________.
40. A very cold winter has left many deer in a population hungry and sick. By the end of the winter, these
populations will likely decrease because of _________________.
41. A deer population experiences growth when the rate of reproduction increases. This change in population
size is due to _________________________.
42. As humans move into a territory, many members of the deer population move away and join other herds;
this movement of individuals out of a population into a new one is called _________________.
43. How does the availability of resources affect population growth?
__________________________________________________________________________________
__________________________________________________________________________________
__________________________________________________________________________________
44. In the spaces below, draw and label the two different types of population curves. Write a brief description of
each next to the graph and give an example.
Description:
Description:
______________________
______________________
______________________
______________________
______________________
______________________
______________________
______________________
______________________
______________________
______________________
______________________
Example:
___________________
Example:
________________
45. What type of growth curve shows a carrying capacity?
46. What type of population growth us a risk for a population crash?
a) Explain why.
_____________________________________________________________________________________
_____________________________________________________________________________________
b) Give an example _______________________________________
47. Detail the key differences between logistic and exponential growth.
Main Idea: Ecological factors limit population growth
48. Define density dependent limiting factor
_____________________________________________________________________________________
49. List three examples of density-dependent limiting factors
_____________________________________________________________________________________
50. Define density- independent limiting factor
_____________________________________________________________________________________
51. List three examples of density-independent limiting factors
_____________________________________________________________________________________
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Invasive Species---Are zebra mussels really invading?
In the mid-1980s a new species found its way to North America. The zebra mussel (Dreissena
polymorpha), a small, clamlike mollusk that grows to about 25 cm as an adult, was introduced into
the waters of the Great Lakes, probably carried in the bilge of a Russian freighter. The zebra mussel
can reproduce in less than a year, and a single female can release 1 million eggs each year. In the
absence of their natural pathogens, parasites, and predators, the zebra mussel populations in the
Great Lakes has grown enormously and are now invading eight major river systems, including the St. Lawrence, Hudson,
Mississippi, Ohio, Illinois, Tennessee, Susquehanna, and Arkansas rivers. The mussels are spread from one body of
water to another by natural flow, carried on the feathers or feet of migrating waterfowl, or by human transport in bait
buckets or on trailered boats. Most of the freshwater systems in North America are now threatened by invasion of the
zebra mussel.
The zebra mussels grow in massive colonies, where nearly a half million individuals may grow on each square meter of
substrate. These colonies encrust the hulls and rudders of ships, the hinges of lock gates, and block the drains and intake
ducts used by industries and power stations. In 1990, for example, Detroit Edison spent over $500,000 to remove zebra
mussels from the intake pipes of its power plants.
The zebra mussels also have severe negative effects on the local ecosystem. As filter-feeders, they take in water and
filter out algae as food, excreting their waste as sediment. A single individual can filter 1 liter of water each day, and a
colony covering 1 square meter of substrate can filter 180 million liters of water per year. Enormous colonies of zebra
mussels can reduce the algal populations of lakes and rivers, thus removing a significant portion of the base of the food
chain and resulting in a decline in the fish populations. Thus, these mussels are a threat to the local biodiversity.
The tremendous filtering capacity of these organisms may have some positive consequences. Zebra mussels have been
a major factor in cleaning Lake Erie after a century of pollution from fertilizers and sewage. After the first 10 years of zebra
mussel existence in Lake Erie, light penetration in the water has increased from only a few centimeters to nearly 10
meters. If these organisms could be controlled, they may become a useful tool in the treatment of sewage and pollution .
52. Which of the following best summarizes the author's main point?
a) Zebra mussels are harmful to the great lakes
b) Zebra mussels are harmful to all lakes
c) The importation of zebra mussels should be regulated
d) Many lakes and river systems are polluted
53. Zebra mussels can move from one lake to another by which method?
a. on the feet of birds
b. carried by the wind
c. moving overland for short periods
d. swimming up canal systems
54. Massive colonies of zebra mussels cause problems because:
a. they destroy the engines of boats
b. they block the flow of water through ducts
c. they produce waste that pollutes the water
d. they eat large amounts of fish
55. Which of the following is a consequence of the zebra mussel population in the great lakes
a. cleaner water
b. decline in algae populations
c. decline in fish populations
d. all of these
56. Why are zebra mussels a problem in the Great Lakes but not in the lake systems where they came from?
a. the other lakes are too cold for them to reproduce in large amounts
b. they have natural predators in the other lakes
c. they cannot leave these lakes
d. they cannot grow into colonies
57. How might zebra mussels be used to improve lake systems?
a. they can be grown as food for humans
b. they can be used to strengthen dams and levies
c. they clean the water of pollutants
d. they remove algae from the water
58. What do zebra mussels eat?
a. algae b. fish c. insects d. water plants
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Nutrient Cycling
Key Concept: Nutrients cycle within ecosystems
Main Idea: matter cycles
Drawing/Sketch
THE WATER CYCLE
59. Name three important needs for water.
60. What draws water back to the Earth?
61. What is transpiration?
62. Name two ways water travels from land to enter the ocean.
THE CARBON CYCLE
63. What is the role of each of the following in the carbon cycle? State an example of each.
a) Primary producers
b) Secondary producers
Drawing/Sketch
c) Decomposers
64. Where is the most of Earth’s carbon located and in what form?
65. How does carbon enter the biotic part of the ecosystem?
66. What functions do plants have in the forest of the ecosystem?
67. How is carbon dioxide returned to the atmosphere?
68. What is a primary producer?
69. What is a fossil fuel?
Drawing/Sketch
THE NITROGEN CYCLE
70. What percent of the air is nitrogen?
71. Why is nitrogen essential to life?
72. How do plants and animals get nitrogen if not from the atmosphere?
73. What are nitrogen fixing bacteria?
74. What is denitrification?
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