APES ap classroom chapter 4
Based on the data in the table, if the number of snakes were to suddenly decrease, which of the following changes would most likely occur in the food web of this ecosystem?
-increase in number of shrews -decrease in number of hawks
Approximate efficiency of the conversion of light energy to chemical energy in photosynthesis
1%
At which time after clear-cutting does the ecosystem exhibit the greatest species richness?
100 years
In a given ecosystem, producers convert solar energy into 15,000kcal of chemical energy stored in organic compounds. Which of the following is the most likely amount of energy available to secondary consumers?
150 kcal
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?
20,000
The atmospheric concentration of carbon dioxide increased from 278 ppm in 1790 to 383 ppm in 2007. What is the approximate percent increase in carbon dioxide concentration from 1790 to 2007?
38%
Which of the following best explains why terrestrial trophic pyramids usually do not have levels higher than tertiary consumers?
A large proportion of energy is lost as heat as it is transferred up the pyramid, so there is not enough energy available to support another level.
Which of the following diagrams correctly illustrates the nitrogen cycle?
A- N2 releases around tree and releases N2 again
Which of the following claims is best supported by the data in the graph?
After the volcanic eruption, pioneer species colonized the area and the ecosystem began to undergo succession.
The largest area of old-growth forest in the United States is located in
Alaska
Plant roots absorb ammonium ions and nitrate ions for use in making molecules such as DNA, amino acids, and proteins.
Assimilation
Which letter correctly identifies a process of the hydrologic cycle in which the phase of water is changed from a liquid to a gas?
B- evaporation
Which environment is characterized by the highest diversity of tree species?
B- graph with high temp and precipitation year round
If the land is later cleared of this invasive species and it is discovered that the soil has an abundance of nitrogen compounds, what conclusion can best be made?
Bacteria in soil and in root nodules converted free nitrogen into nitrogen compounds.
Which of the following world regions contain the greatest area of rain forest?
Brazil and Indonesia
The location of the greatest remaining natural biodiversity
Brazil-E
Which environment is most likely to be characterized by dry scrub with frequent fires?
C- low temp and precipitation in summer months
Marine sediments that form limestone are a major sink for this element.
Carbon
Which of the following is true of carbon as it cycles in nature?
Carbon sinks include forests and oceans.
How does the burning of fossil fuels contribute to the net increase in atmospheric carbon?
Carbon that has been sequestered underground is added to the carbon cycling between the atmosphere and the biosphere.
Which letter correctly identifies the part of the hydrologic cycle that is most directly affected by impervious building materials, such as concrete and asphalt?
D- on land
Which of the following categories of organisms, which are required for the cycling of matter in an ecosystem, is missing from the table?
Decomposers
Based on the diagram above, which process most directly results in the storage of carbon as coal and oil over millions of years?
Decomposition
Nitrate ions and nitrite ions are converted into nitrous oxide gas and nitrogen gas (N2).
Denitrification
The process by which a soil nutrient is reduced and released to the atmosphere as a gas
Denitrification
Which of the following pathways indicate how nitrogen is added to the largest nitrogen reservoir?
Denitrifying bacteria and volcanic activity
Which of the following is an example of a carbon sink?
Deposition of organic matter on the deep ocean floor
This biome contains plants that are adapted to prevent water loss due to the low average rainfall and high temperatures year-round.
Desert
Which of the following best describes the movement of energy in an ecosystem?
Energy is harnessed by producers, and available energy decreases with each trophic level transfer.
Scientists calculated the net primary productivity at two different forest sites. Both forests have the same gross primary productivity. Forest A has a net primary productivity of 1,650kcal/m2/year, and forest B has a net primary productivity of 1,110kcal/m2/year. Which of the following statements is best supported by the data?
Forest A producers have lower rates of cellular respiration than forest B producers.
Which of the following is a process that indirectly removes carbon from Earth's atmosphere?
Formation of carbonate deposits
Which of the following statements is true of aquatic biomes?
Freshwater biomes are a vital source of drinking water.
Which of the following best describes gross primary productivity in an ecosystem?
Gross primary productivity is the total amount of solar energy captured by producers through photosynthesis over time.
Based on the data in the table, which of the following pairs of organisms has two ecological relationships, both competition and predation?
Hawks and snakes
Which of the following changes in the hydrologic cycle is most likely to occur as a result of the change in vegetation in the area?
Increased infiltration
Which of the following best describes a symbiotic relationship?
Intestinal bacteria inhabit the gut of humans.
Which of the following best illustrates an abiotic component of the environment affecting a biotic component of the environment?
Low phosphorus content in soil limits the growth of vegetation.
Which of the following best describes the net primary productivity of an ecosystem?
Net primary productivity is the amount of energy lost through respiration by producers subtracted from the gross primary productivity of an ecosystem.
Photosynthesis is the major source of which of the following gases in Earth's atmosphere?
O2
A North Carolina timber company proposes to clear-cut 45 hectares of oak-hickory deciduous forest in the Appalachian Mountains. The company has said that the forest will regrow naturally, and 50 years after the clear-cutting the company plans to harvest again, cutting all the oaks and hickories that have at least a 40-centimeter diameter. A local citizens' group claims that this is not a realistic plan. Which of the following, if true, best supports the claim of the citizens' group?
Oak and hickory are late-successional species; pioneer species will dominate for many decades before the oaks and hickories are reestablished.
Of the following ecosystems, which has the lowest net primary productivity, measured as kilocalories of energy produced per square meter per year?
Open ocean
Guano from fish-eating birds is a commercial source of this element.
Phosphorus
Which of the following elements is most likely to limit primary production in freshwater lakes?
Phosphorus
Which of the following would best describe X in the diagram above?
Phosphorus and nitrogen are both required for plant growth.
The process in which glucose is synthesized by plants
Photosynthesis
In a typical forest ecosystem, dead trees and fallen trees are most important because of their role in which of the following?
Providing habitats for wildlife
According to the diagram, the movement of phosphorus between biological organisms and soil is in a steady state in an undisturbed system. Which of the following best explains the reason for this steady movement?
Readily available organic phosphorus in the soil is assimilated by plants.
Based on the data shown in the graph, which of the following best describes how ecologists could determine when this ecosystem is approaching a climax community?
Record the number and type of producers present every year after the eruption
Which of the following best explains why the different warbler species can all have habitats in the same conifer trees?
Resource partitioning of the seeds reduces competition, and the five different species can live in the same tree.
Country with the largest area of boreal forests
Russia
This biome is characterized by long dry seasons and is dominated by grasses, shrubs, and grazing animals.
Savanna
Which of the following is the best example of a keystone species?
Sea otter
The great grasslands of the world have which of the following primary characteristics in common?
Seasonal cycles of temperature and precipitation produce abundant vegetative growth.
Based on the diagram, which of the following reservoirs contains the most phosphorus?
Sediments
Which tree species grows best with full sunlight?
Sweet Gum
Which of the following statements best explains why only a limited number of offspring can survive in a fish population?
The chance of survival decreases when there is intraspecific competition for resources among surviving yearlings.
Which of the following is a characteristic of tropical rain forests?
Their soils are relatively poor in nutrients.
Which of the following is the best explanation for why there is such a small amount of phosphorus that moves into aquatic systems?
There is not a gaseous phase of the phosphorus cycle, and therefore the movement of phosphorus into oceanic reservoirs is very slow.
Which of the following best describes soil in many tropical rain forests?
They are quickly depleted nutrients when the forest is removed.
Why do introduced species often become pests?
They displace native species.
Which of the following best explains why decomposers in soils and water are important to ecosystems?
They recycle nutrients.
All of the following statements about invasive exotic species are true EXCEPT:
They tend to have low reproductive rates.
This biome is warm and wet, with little seasonal variation in temperature and frequent precipitation.
Tropical rain forest
Which of the following best helps to explain why phosphorus is often a limiting factor in many ecosystems?
Under many conditions, phosphorus forms stable insoluble compounds.
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
an increase in both mean annual temperature and mean annual precipitation
Elements that cycle in the environment and that also have a gaseous phase at some point in their cycle include which of the following?
carbon and sulfur
Exemplified by moss growing on a tree trunk in a forest
commensalism
Exemplified by starlings displacing bluebirds from nesting sites
competition
The graph below shows the results obtained when two species of Paramecium were grown together in the same medium. The graph above best exemplifies
competitive exclusion
Of the following organisms, which occupies the lowest trophic level?
deer
Decreased by the breakdown of organic waste
dissolved oxygen
For a primary producer, the main function of photosynthesis is to manufacture
glucose
In Mediterranean climate regions like portions of California, a wetter-than-normal winter often leads to greater severity of fires the following summer. This seeming paradox occurs because increased rain leads to
greater accumulation of chapparal biomass
Which of the following would likely reduce the threats posed by exotic species to native species?
i-Increasing inspections of goods coming into a country iii-Enforcing legislation that restricts imported materials such as untreated wooden packing crates
Reasons that the population size of an exotic species often grows rapidly when the species is introduced in a new environment include which of the following?
ii- there is large underutilized food source in the new environment iii- the exotic species has few natural predators in the new environment
Open oceans produce the largest share of Earth's biomass because the net primary productivity (NPP) of the oceans is
low, but the large expanse of the oceans supports enormous numbers of producers such as phytoplankton
Exemplified by bees consuming nectar and carrying pollen from one flower to another
mutualism
Ammonia is converted to nitrite, then to nitrate.
nitrification
The major reservoirs of nitrogen and sulfur in the biosphere are correctly identified by which of the following?
nitrogen->atmosphere sulfur->rocks
Exemplified by ticks feeding on a deer
parasitism
Based on the diagram above, which of the following processes reduces the amount of carbon dioxide in the atmosphere?
photosynthesis
The two major processes involved in the carbon cycle are
photosynthesis and respiration
The terrestrial biomes shown in the diagram above vary in net primary productivity. The explanation for the variation includes which of the following?
temperature and precipitation
The ultimate source of energy for terrestrial ecosystem is
the Sun
Population biologists are concerned about introduced species such as the zebra mussel in North America because
the introduced species compete for resources more effectively than native species
Which of the following major storage reservoirs of carbon, stored in the form of carbon dioxide, is not represented in this diagram?
the ocean
The process in the hydrologic cycle in which water vapor is released from leaves into the atmosphere is called
transpiration