1. Unit 12 Ecology & Human Impact ]
Rewind your mind
Unit Ecology & Human Impact ]

2. 1) Which of the following is largest level of organization in ecology, made up of biotic and abiotic factors?
A. Population C. Community
B. Organism D. Ecosystem

3. D. Ecosystem

4. 2) In the marshlands of the northeastern United States, the purple loosestrife plant has replaced many native plants. The success of the purple loosestrife plant is most likely due to its ability to:
Control secondary consumers
Conserve natural resources
Transfer energy from soil minerals
Compete for abiotic factors

5. D. Compete for abiotic factors

6. Which of the following is a biotic factor in the environment of a fresh water fish?
The amount of light penetrating the water
The temperature of the water
The mud on the bottom of the pond
The algae growing in the water

7. D. The algae growing in the water

8. Mutualism C. Commensalism Predator-Prey D. Parasitism
Bacteria living in nodules on the roots of legumes have the ability to fix atmospheric nitrogen into a water-soluble form that plants can use. The bacteria absorb sugar from the plants’ roots. Which describes the relationship between the bacteria and the legume plants?
Mutualism C. Commensalism
Predator-Prey D. Parasitism

9. Mutualism

10. The large amount of salt in the air and water of coastal areas determines which species can exist there. In these areas, the salt functions as a
Source of energy C. Food source
Biotic factor D. Limiting factor

11. D. Limiting factor

12. 6) In which quadrant would there be the most density-dependent limiting factors, like competition?
Quadrant A
Quadrant B
Quadrant C
Quadrant D

13. D. Quadrant D

14. An ecologist observes a trend among two organisms
An ecologist observes a trend among two organisms. The trend shows that shortly after the population of one organism increases, the population of the other organism decreases. Likewise, the trend shows that after the change occurs, the number of the first group of organism then begins to decline. This ecologist is most likely observing the population trend in which relationship?
Mutualism C. Commensalism
Predation D. Parasitism

15. B. Predation

16. 8) A community is studied and several interactions are observed and recorded. Which type of interaction could illustrate the process of parasitism?
Interaction A C. Interaction C
Interaction B D. Interaction D

17. B. Interaction B

18. 9) The graph below represents population growth in a specific population.
What most likely explains the change in the graph that occurs at point C?
The death rate of the population has increased.
The population has reached its carrying capacity.
The population is growing exponentially.
Infant mortality of this population has increased.

19. B. The population has reached its carrying capacity.

20. 10) Which of the following would result in the graph shown below?
Variety of predators
Habitat destruction
Unlimited resources
Competition for abiotic factors

21. C. Unlimited resources

22. Which of the following is not recycled in an ecosystem?
Which of the following is not recycled in an ecosystem?
Carbon C. Water
Energy D. Nitrogen

23. B. Energy

24. Because vultures feed mainly on organisms that they have not killed, they are known as what type of organism?
Predators C. Omnivores
Scavengers D. Autotrophs

25. B. Scavengers

26. Species of organisms that obtain food by only eating autotrophs are known as
Tertiary consumers
Producers
Herbivores
Secondary consumers

27. C. Herbivores

28. Why do ecosystems rarely contain more than a few tropic levels?
Energy transfer efficiency is high
Energy transfer efficiency is low
Energy amounts remain constant
Energy cannot flow through levels

29. B. Energy transfer efficiency is low

30. 15) Which diagram best represents the recycling of matter in the carbon cycle?

31. A

32. 16) The mouse population would most likely decrease if there were
A decrease in the snake and hawk population
An increase in the frog and tree population
A decrease in the amount of available sunlight
An increase in the number of decomposers

33. C. A decrease in the amount of available sunlight

34. Which organisms would have the greatest amount of biomass?
Snake and hawk C. Cricket and mouse
Grass and trees D. Frog and deer

35. B. Grass and trees

36. 18) What is the original source of energy for this food web?
Chemical bonds in sugar molecules
Enzymatic reactions
Sunlight
Chemical reactions of bacteria

37. C. Sunlight

38. 19) Which organisms are not shown above, but are essential to a balanced ecosystem?
Heterotrophs C. Producers
Autotrophs D. Decomposers

39. D Decomposers

40. 20) Gardeners sometimes use traps to capture slugs. Organisms found in the trap after being in the garden for one week are shown in the table. Based on the table, how many of the organisms were herbivores?
C. 22
9 D. 99

41. C. 22

42. Which factor is often responsible for the other three?
Increase in levels of toxins in both water and air
Increase in human population
Increased poverty and malnutrition
Increased depletion of finite resources

43. B. Increase in human population

44. Enditron is a company that has decided to expand their production and build a new factory. Which of the following human activities will Enditron partake in that contributes the most to global warming?
Cutting down trees to clear a space for the factory.
Burning fossil fuels to power the factory.
Using chlorofluorocarbons in aerosol cans
Increasing the amount of CO2 by human respiration in the area.

45. B. Burning fossil fuels to power the factory.

46. 23) Which situation would result in the greatest increase in the human population?
Decreased birth rate and increased death rate
Increased infant mortality and decreased death rate
Medical advances and better nutrition
Increased birth rate and decreased medical advances

47. C. Medical advances and better nutrition

48. 24) Air pollution is contributing to an environmental problem, especially harmful to plants, known as which of the following?
Deforestation
Greenhouse effect
Acid rain
Biological magnification

49. C. Acid rain

50. 25) Which trophic level would the concentration of pesticide DDT be the highest?
Producers
Primary consumers
Secondary consumers
Tertiary consumers

51. D. Tertiary consumers

52. 26) Which of the following best describes the effects of ozone depletion?
Increasing amounts of UV radiation reaching Earth’s surface
Decreasing amounts of UV radiation reaching Earth’s surface
Increasing amounts of CO2 in Earth’s atmosphere
Decreasing amounts of CO2 in Earth’s atmosphere

53. Increasing amounts of UV radiation reaching Earth’s surface

54. Deforestation will most directly result in an immediate increase in
Atmospheric carbon dioxide
Atmospheric ozone
Wildlife populations
Renewable resources

55. A. Atmospheric carbon dioxide

56. Hydrilla is a nonnative water plant that is rapidly spreading in the southern US. It crowds out native species. Which statement best explains the success of the hydrilla?
Hydrilla is not as affected as local plants by native limiting factors
Plants from other countries are harder to kill than hydrilla
Hydrilla thrives in the unpolluted water in the lakes
The climate is better than that of the hydrilla’s original habitat

57. Hydrilla is not as affected as local plants by native limiting factors

58. 29) Which of the following describes a goal of sustainable development, that humans must strive to attain?
Conserving resources without considering the needs of the human population
Meeting human needs without causing long-term harm to the environment
Using natural resources without considering how it affects the environment
Increasing the amount of global desertification and soil erosion

59. Meeting human needs without causing long-term harm to
the environment

60. 30) The age structure diagram below represents what type of population growth?
Rapidly decreasing
Stable
Rapidly increasing
Slowly increasing

61. C. Rapidly increasing