APES Final Review

Which of the following best describes a symbiotic relationship?

Intestinal bacteria inhabit the gut of humans.

The major reservoirs of nitrogen and sulfur in the biosphere are correctly identified by which of the following?

Nitrogen: Rocks, Sulfur: Vegetation

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.

At which time after clear-cutting does the ecosystem exhibit the greatest species richness?

100 years

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

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.

Based on the theory of island biogeography, which of the following would most likely experience the greatest decline of specialist species if an invasive species emigrated from the mainland?

A small island in close proximity to the mainland

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 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.

Directions: Select the choice that best fits each statement. The following question(s) refer to the following possible relationships between organisms in an ecosystem. Exemplified by moss growing on a tree trunk in a forest.

Commensalism

Directions: Select the choice that best fits each statement. The following question(s) refer to the following possible relationships between organisms in an ecosystem. Exemplified by starlings displacing bluebirds from nesting sites.

Competition

Which of the following categories of organisms, which are required for the cycling of matter in an ecosystem, is missing from the table?

Decomposers

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

Deer

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/year1,650kcal/m2/year, and forest B has a net primary productivity of 1,110kcal/m2/year1,110kcal/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 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

The terrestrial biomes shown in the diagram above vary in net primary productivity. The explanation for the variation includes which of the following? I. Temperature II. Precipitation III. Longitude

I and II only

Five islands, A, B, C, D, and E, differ only in distance from the mainland, area, and species diversity. Which island would be predicted to have the highest species diversity?

Island B, Distance from Mainland: 50, Area (hectares): 1 x 10^6

Directions: Select the choice that best fits each statement. The following question(s) refer to the following possible relationships between organisms in an ecosystem. Exemplified by bees consuming nectar and carrying pollen from one flower to another.

Mutualism

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.

Which of the following statements best describes why it is predicted that the orchid mantis will be more affected by global climate change than the tropical cockroach will be?

Orchid mantises tend to be advantaged in habitats that remain constant; the rain forest habitat is likely to shift because of global climate change.

Which of the following would best describe X in the diagram above?

Phosphorus and nitrogen are both required for plant growth.

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 would be categorized as a cultural ecosystem service of forests?

Recreation and scenic areas for tourism

Salamanders, ospreys, snapping turtles, and beavers all live in aquatic habitats. Salamanders lay their eggs in small freshwater pools and feed on insects. Osprey habitats include rivers, bays, and swamps and the birds feed on fish and other animals in the water or on land. Snapping turtles live in fresh or brackish water and feed on plants, fish, frogs, and snakes. Beavers build lodges on islands, pond banks, and lake shores and eat a variety of shrubs, grasses, and crops. Based on the information provided above, which of the following species would best be classified as a specialist?

Salamanders

Which of the following examples illustrates the community with the highest biodiversity?

Species Number of individuals A 10 B 10 C 10 D 10 E 10

Which tree species grows best with full sunlight?

Sweet gum

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.

The table below shows measurements of the beak size of a sample of ten ground finches on each of two islands in the Galápagos archipelago. The two islands are about ten kilometers apart, and all the birds are the same species. Given that beak size is genetically determined, which of the following hypotheses is the most likely explanation for the differences in data between the islands?

The types of food found on the two islands exert selective pressure on beak size.

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 explains why decomposers in soils and water are important to ecosystems?

They recycle nutrients.

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.

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

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

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 shrewsdecrease in number of hawks

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