Science 10 Ecology
Unit Questions

1. Define: ecosystem

2. a) Which area would have the larger biodiversity, forest, lawn, a patch of pavement?
b) Explain their differences in biodiversity.

3. Define: niche

4. a) Give two examples of niches.
b) Do you have a niche in school? at home?

5. What circumstances may lead to increased competition among organisms for a niche?

6. What may be the result of competition for the niche?

7. Contrast biotic and abiotic elements of an ecosystem.

8. a) What is the role of an indicator species.
b) Why are frogs useful as such a species?

9. What factors can impact the health of a frog community?

10. You are a conservationist discussing plans for a new subdivision with the developer. The site is a wide swampy area with a rich biodiversity, including frogs, an indicator species. Describe how the following aspects of the development may affect frogs.
a) clearing away all the trees, shrubs and grasses
b) draining the swamp
c) filling in low areas with gravel and paving over many sections
d) building a road through the center of the swamp so the two sides are now joined
e) the engines in the pieces of construction equipment releasing many fumes into the air

11. a) What is an ecotone?
b) Give an example of an ecotone.

12. In general, what does a food chain or web show us?

13. Sketch and label a generalized food chain containing: grasshoppers, worms, shrubs and other plants, rabbits, snakes, hawks, robins and frogs.

14. Contrast the food types of herbivores, carnivores and omnivores.

15. Which type of consumer might be more successful?

16. Which is self-sufficient, a hetero- or an autotroph?

17. a) Which part of the food chain has the least biomass?
b) Why?

18. What is the simplest reason a population declines?

19. What is the more realistic reason?

20. What is the worst case of population decline?

21. Why do paleontologists think dinosaurs became extinct?

22. How are endangered populations helped to increase in size?

23. What is the cause of modern extinctions?

24. Is it easy to reestablish the biodiversity of some ecosystem?

25. a) What is an introduced species?
b) In general, what may be the effect of an introduced species on the existing food chain?

26. Where should we look for the best modeling of recycling?

27. List the sources of CO₂ in the carbon cycle.

28. List the sinks (where something is used up) of CO₂ in the carbon cycle.

29. What process allows plants to obtain C?

30. What is the main combustible element in plants?

31. What gas is the major component of the atmosphere?

32. What are two ways in which N₂ gas is fixed?

33. What is the product of nitrogen fixation?

34. a) Nitrifying bacteria use what chemical?
b) what chemical do they create?

35. What form of nitrogen can be used by plants?

36. What is the product of ammonification?

37. What is the role of denitrifying bacteria?

38. Make a simple sketch of the oxygen cycle.

39. What is a pesticide?

40. Is it easy to define which organisms are pests?

41. What is a first generation pesticide?

42. a) What is an advantage of modern pesticides?
b) What is a drawback?

43. What organisms are killed by: a) insecticides b) herbicides c) fungicides d) bactericides?

44. How is bioamplification created by the operation of a food chain?

45. Create an activity to show bioamplification.

46. a) Why do we say plants are the lungs of the Earth?
b) In general, soils are generally deep. T,F.

47. a) Soil is divided into how many layers?
b) Name them from the top down.

48. Which soil layer? a) middle b) concentrated minerals c) dark color d) decomposed grass (e) humus f) top g) light colored h) deepest i) nutrient supply j) few rocks k) many rocks

49. a) Name the two types of weathering.
b) Is soil creation a quick thing?

50. Water on the surface is called ___ while water that has percolated down into the soil is called ___.

51. You want to dump chemicals onto the back section of your property, out of sight. Your neighbours are alarmed but it is, after all, your own land. Their concern is that leeching will contaminate the ground water for the entire community. What are they talking about?

52. How do plants adapt to the problem of nutrients being leeched down into deep soil layers?

53. You are an assistant archaeologist at a "dig" in a low lying field not too far from an old lake bed. The head scientist says she hopes the water table will not be a problem. What is she talking about?

54. What is a biome?

55. Around the globe, there are how many major biomes?

56. Canada contains how many biomes?

57. Which biome? a) thick soils b) thin undergrowth c) permafrost d) dwarf shrubs e) huge biodiversity f) lions g) moose h) many types of grasses i) cacti j) black bear k) around equatorial belt l) frequent fires m) North Africa n) dense canopy

58. You are a travel agent. Which biomes would you advise a person not to visit if they:
a) hate heavy clothes b) love a wide open view all around c) hate sweating all the time
d) are scared of large, fast slinking predators e) hate thorny plants f) are scared of fires
g) hate having to push through undergrowth h) hate ice and snow.