APES

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

Primary producers in a lake ecosystem store approximately 25,000 kcal/m2/yr of energy in their biomass. Which of the following identifies the most likely amount of energy available to a tertiary consumer in this ecosystem?

25 kcal/m2/yr

The net primary production of a pine forest on a lava flow on Mount Fuji is about 175,000kcal/m2/yr, and the plant respiration is estimated to be 115,000kcal/m2/yr. What is the total amount of energy transferred during photosynthesis for this ecosystem?

290,000kcal/m2/yr

Algae in an aquatic food chain convert solar energy into 93,000 kilocalories of plant tissue. Which of the following values best represents the amount of energy available for primary consumers in the food chain?

9,300 kilocalories

Algae in an aquatic food chain convert solar energy into 93,000 kilocalories of plant tissue. Which of the following values best represents the amount of energy available for secondary consumers in the food chain?

930 kilocalories

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 best shows the process of evolution?

A population of mosquitoes develops resistance to a pesticide

Which of the following statements about levels of biodiversity is correct?

A population with high genetic biodiversity is better able to respond to environmental stressors.

Plant roots absorb ammonium ions and nitrate ions for use in making molecules such as DNA, amino acids, and proteins.

Assimilation

A field is abandoned, and an invasive plant that can live in nutrient-poor soil moves into the field. 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

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.

Of the following organisms, which occupies the lowest trophic level?

Deer

Two branches of a river have different sediment loads. Based on the diagram, which of the following most likely led to the differences in the amount of sediment in the two branches of the river?

Deforestation from clear-cutting

Which process in the nitrogen cycle releases nitrogen gas into the atmosphere?

Denitrification of soil nitrates by bacteria

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 can be used to assess the biological diversity of an area?

Genetic variation within each species and number of species present

A research team monitoring a local freshwater ecosystem noticed that over the past few years the otter population had declined significantly, while the populations of other species remained fairly constant. After running tests, the research team determined that mercury levels in invertebrates and small fish in the ecosystem were very high. In this ecosystem, what role did the otters occupy?

Indicator species

The many finch species of the Galápagos Islands evolved from a single species that immigrated to the islands from the coast of South America. These species differ primarily in beak shape, which is closely related to the type of food each species specializes in eating. Which of the following best explains why each of the finch species on the Galápagos Islands evolved to be specialists?

Islands have limited food resources, forcing species to feed on a small range of food items.

The pioneer species most likely to occur in secondary succession might be:

Legume

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.

Ammonia is converted to nitrite, then to nitrate.

Nitrification

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.

Guano from fish-eating birds is a commercial source of this element.

Phosphorous

Which of the following would be categorized as a cultural ecosystem service of forests?

Recreation and scenic areas for tourism

Which of the following interactions between the warbler species is shown in the diagram?

Resource partitioning

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

Which of the following best describes why secondary succession generally occurs more quickly than primary succession?

Secondary succession takes place in areas that already have soil and nutrients in place, whereas primary succession occurs in areas that lack soil.

For which of the following reasons do small isolated islands have a greater rate of species extinction than larger, less isolated islands?

Small isolated islands have a lower availability of resources.

A one-hectare pond is sampled in early September. The sample yields 1 small catfish as well as 17 benthic invertebrates that represent 10 species. If the pond is resampled a year later, which of the following would best indicate that the pond had been adversely affected by adjacent development?

The biodiversity of the pond has decreased.

In a fish species, the number of eggs that hatch and survive for one year varies depending on the number of eggs that were produced. As the number of eggs produced increases past a threshold number, the survival rate of the offspring decreases. 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.

In England approximately 250 years ago, the peppered moth had light-colored wing patterns that camouflaged them against the light-colored trees. Over time in urban areas, the number of peppered moths with dark-colored wings increased as pollution from the Industrial Revolution darkened the trees the moths rested on. Which of the following statements best describes how the moths adapted to the new environment over time?

The moths adapted to the new environment by changes in the genetics of the population.

Which of the following biogeochemical cycles is correctly paired with its largest reservoir?

The nitrogen cycle and the atmosphere

The Devils Hole pupfish is one of the world's rarest fishes, spending most of its life in the top few meters of very warm waters of a cavern located in the middle of the Mojave Desert. Devils Hole, a geologic pool, is the only naturally occurring habitat for the endangered Devils Hole pupfish. This fish's habitat is one of the smallest natural ranges known for any vertebrate. Devils Hole is an extreme environment, with water temperatures and dissolved oxygen concentrations near the lethal limits for most fish species. Which of the following statements best explains why the Devils Hole pupfish are able to live in this environment?

The pupfish are well adapted to the habitat of Devils Hole and can thrive in conditions that are outside of the range of tolerance for most other species.

A one-hectare pond is sampled in early September. The sample yields 1 small catfish as well as 17 benthic invertebrates that represent 10 species. Which of the following can be estimated from the sample for the invertebrates in the pond?

The species richness

Which of the following is a measure of the biodiversity of an ecosystem?

The total number of different plant species

Which of the following is a characteristic of tropical rain forests?

Their soils are relatively poor in nutrients.

Based on the theory of island biogeography, which of the following is the most likely reason that an island in the ocean that is 5 kilometers from a continent would have a higher number of species than one that is 15 kilometers from a continent?

There are more species that have the ability to travel 5 kilometers than can travel 15 kilometers.

This biome has the highest net primary productivity, in part because of consistently warm temperatures and abundant sunlight.

Tropical rainforest

The underlying subsoil of this biome is permafrost, which prevents both water draining through and deep-rooted plants from growing. Additionally, there is very little precipitation per year.

Tundra

A student reads that nanosilver particles are used in cosmetics to allow nutrients to penetrate deeper into the skin. When the cosmetics are washed off, the nanosilver particles can enter freshwater ecosystems. These particles may decrease survival in many aquatic organisms. The student determines that Daphnia magna, a tiny freshwater crustacean widely found in North America, might make a good test subject for an experiment. Which statement below is the most likely testable hypothesis based on the information provided?

When the concentration of nanosilver particles in water is increased, the population of Daphnia magna will decrease.

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

Marine sediments that form limestone are a major sink for this element.

carbon

Exemplified by starlings displacing bluebirds from nesting sites

competition

The consumption of mosquitoes by bats and the control of flooding provided by tropical forests in mountainous areas of Central America are examples of

ecosystem services

For a primary producer, the main function of photosynthesis is to manufacture

glucose

In North America, native pollinators often increase the quantity and quality of crops of native plants that are insect pollinated more effectively than European honeybees do. The most likely reason for the phenomenon is that native pollinators

have coevolved with native plant species

Exemplified by bees consuming nectar and carrying pollen from one flower to another

mutualism

Of the following ecosystems, which has the lowest net primary productivity, measured as kilocalories of energy produced per square meter per year?

open ocean

Exemplified by ticks feeding on a deer

parasitism

Which of the following elements is most likely to limit primary production in freshwater lakes?

phosphorus

The process in which glucose is synthesized by plants

photosynthesis

The two major processes involved in the carbon cycle are

photosynthesis and respiration

The major biological source of dissolved oxygen in the ocean comes from

photosynthesis by phytoplankton

Phytoplankton are most abundant in the upper few hundred feet of most bodies of water because

sunlight does not penetrate to great depths in water

The process in the hydrologic cycle in which water vapor is released from leaves into the atmosphere is called

transpiration

This biome is warm and wet, with little seasonal variation in temperature and frequent precipitation.

tropical rain forest