24.
Traveling southward from the Arctic regions of Canada to the tropics of Panama, one passes through several biomes - tundra, coniferous forest, temperate deciduous forest, and tropical rain forest. This pattern of change in vegetation is primarily the result of
(A) primary and secondary succession
(B) the invasion of exotic species
(C) an increase in mean annual temperature and a decrease in mean annual precipitation
(D) an increase in both mean annual temperature and mean annual precipitation
(E) an increase in the total annual hours of sunlight
(D) an increase in both mean annual temperature and mean annual precipitation
25. Which of the following best illustrates an abiotic component of the environment affecting a biotic component of theenvironment?
(A) Composted manure is added to agricultural soil during spring tilling.
(B) Coral reefs modify the direction of an ocean current.
(C) Plants release O2 into the atmosphere during photosynthesis.
(D) Low phosphorus content in soil limits the growth of vegetation.
(E) A thick planting of ground cover reduces soil erosion on a hillside.
(D) Low phosphorus content in soil limits the growth of vegetation.
26. Guano from fish-eating birds is a commercial source of this element.
(A) Carbon
(B) Sodium
(C) Sulfur
(D) Phosphorus
(E) Potassium
(D) Phosphorus
27. Marine sediments that form limestone are a major sink for this element.
(A) Carbon
(B) Sodium
(C) Sulfur
(D) Phosphorus
(E) Potassium
(A) Carbon
28. The net annual primary productivity of a particular wetland ecosystem is found to be 8,000 kcal/m2 per year. If respiration by the aquatic producers is 12,000 kcal/m2 per year, what is the gross annual primary productivity for this ecosystem, in kcal/m2 per year?
(A) 4,000
(B) 8,000
(C) 12,000
(D) 20,000
(E) 96,000
(D) 20,000
29. Which of the following is a process that indirectly removes carbon from Earth's atmosphere?
(A) Formation of carbonate deposits
(B) Outgassing by volcanoes
(C) Respiration by mammals
(D) Respiration by anaerobic bacteria
(E) Photodissociation by ultraviolet light
(A) Formation of carbonate deposits
30. Which of the following is true of carbon as it cycles in nature?
(A) Carbon dioxide is released during photosynthesis.
(B) Carbon compounds rarely exist in the gaseous state.
(C) Carbon sinks include forests and oceans.
(D) The carbon dioxide concentration in the atmosphere is reduced by cutting trees.
(E) Carbon is concentrated in igneous rocks.
(C) Carbon sinks include forests and oceans.
31. Which of the following is an example of a carbon sink?
(A) Deposition of organic matter on the deep ocean floor
(B) Clearing of trees in the Amazon forest
(C) Combustion of fossil fuels in power plants
(D) Decomposition of food waste by bacteria
(E) Nutrient uptake by the roots of grasses in a suburban lawn
(A) Deposition of organic matter on the deep ocean floor
32. The great grasslands of the world have which of the following primary characteristics in common?
(A) They are restricted in occurrence to the region between 30° north latitude and 30° south latitude.
(B) Due to high humidity, fires are uncommon and rarely affect large areas.
(C) They are typically created by overgrazing by livestock.
(D) Seasonal cycles of temperature and precipitation produce abundant vegetative growth.
(E) High winds blow seeds of trees away such that only grasses exist
(D) Seasonal cycles of temperature and precipitation produce abundant vegetative growth.
33. Members of an r-selected species characteristically
(A) grow slowly
(B) produce few offspring
(C) reach sexual maturity quickly
(D) have long life spans
(E) are very protective of their offspring
(C) reach sexual maturity quickly
34. Correct statements about the northern spotted owl include which of the following?
I. It is a pioneer species that is an opportunistic feeder.
II. It is dependent on mature, old-growth forest for its habitat.
III. It is a carnivore at or near the top of the food chain.
(A) I only
(B) II only
(C) III only
(D) I and II
(E) II and III
(E) II and III
35. Which of the following is a characteristic of tropical rain forests?
(A) They rarely receive more than 100 centimeters of rain per year.
(B) Their soils typically have a high pH.
(C) Their soils are relatively poor in nutrients.
(D) They do not exhibit a great deal of species diversity.
(E) They generally occur in the rain shadows of mountain ranges.
(C) Their soils are relatively poor in nutrients.
see graphs in day 2 packet
36. Which environment is most likely to be characterized by dry scrub with frequent fires?
(A) A
(B) B
(C) C
(D) D
(E) E
(C) C
see graphs day 2 packet
37. Which environment is characterized by the highest diversity of tree species?
(A) A
(B) B
(C) C
(D) D
(E) E
(B) B
38.
The graph below shows the results obtained when two species of Paramecium were grown together in the same medium:
see day 2 packet for graph
The graph above best exemplifies
(A) the demographic transition
(B) sustained logarithmic growth
(C) the edge effect
(D) competitive exclusion
(E) the normal distribution
(D) competitive exclusion
39. Country with the largest area of boreal forests
(A) Australia
(B) Brazil
(C) Chile
(D) Russia
(E) United States of America
(D) Russia
40. Country with the largest area of temperate deciduous forest
(A) Australia
(B) Brazil
(C) Chile
(D) Russia
(E) United States of America
(E) United States of America
41. The crude growth rate, r , of a population is calculated by
(A) multiplying the existing population size by life expectancy
(B) dividing the crude birth rate by 2
(C) dividing the doubling time by 70
(D) adding the crude birth rate to the crude death rate
(E) subtracting the crude death rate from the crude birth rate
(E) subtracting the crude death rate from the crude birth rate
42. In a typical forest ecosystem, dead trees and fallen trees are most important because of their role in which of
(A) Providing a valuable source of timber
(B) Providing habitats for wildlife
(C) Contributing to soil erosion
(D) Increasing water runoff
(E) Removing carbon dioxide from the air
(B) Providing habitats for wildlife