APES: ALL AP Classroom MCQ's (Units 1-4.1)

Which of the following processes is illustrated by the downward arrows from the atmosphere that show the conversion of nitrogen gas into usable forms available to produce?

B) Nitrogren fixation

- Nitrifying bacteria or lighting converts atmospheric nitrogen N2 to ammonia.

Which of the following types of organisms are required to complete the nitrogen cycle, including the process of denitrification?

A) Bacteria

- Certain bacteria are specialized in fixing nitrogen, in association with plants such as soybeans and other legumes. Other types of bacteria perform nitrification: converting ammonium ions into nitrite ions, and then into nitrate ions. Finally, other bacteria perform denitrification, the reduction of nitrates back into nitrogen gas

The majority of the nitrogen on Earth can be found in which of the following reservoirs?

C) The atmosphere

- The largest reservoir of nitrogen is the atmosphere

Which of the following best identifies a key component of the hydrologic cycle that powers the movement of water and is missing from the diagram?

B) The Sun

- The Sun powers the movement of water through evaporation and transpiration

Which of the following major reservoirs of freshwater are missing from the diagram?

C) Ice caps

- Ice caps (and glaciers) store almost 70% of the Earth's total freshwater

Which of the following best describes what is represented by the arrows in the food web?

B) The flow of energy

- Arrows in a food web depict the flow of energy between trophic levels

Which trophic level has the least available energy in kilojoules in this food web?

D) Killer whale

- The amount of energy available decreases up the food chain, so the organisms at the highest trophic level would have the fewest kilojoules of energy available. The killer whale is a top predator (quaternary consumer)

Based on the second law of thermodynamics, how much biomass of phytoplankton would be needed to produce 1 kilogram (kg) of large fish in this food web?

D) 1,000 kg

- Assuming only approximately 10% of biomass is available to be transferred to the next trophic level, 1,000kg of phytoplankton would be needed because of the four different energy transfers in this food web. (1,000kg) phytoplankton ×0.10=100kg available to herbivorous zooplankton; 100kg zooplankton ×0.10=10kg available to small fish; 10kg small fish ×0.10=1kg of large fish biomass]

Six white-tailed deer and six sika deer were enclosed in a pasture for observation during an eight-year study in central Texas. White-tailed deer are a native species to central Texas, while sika deer are a nonnative species to central Texas. White-tailed deer feed on flowering plants and the tips of trees and shrubs but do not eat grass. Sika deer feed on flowering plants, the tips of trees and shrubs, and grass. All other grazing animals were kept out of the pasture during the study. The number of sika deer more than doubled after the eight years, while the population of white-tailed deer decreased by 50 percent.

Which of the following statements best supports the results from the study?

B) The sika deer out competed the white-tailed deer in consuming flowering plants and shrubs

- Since both species eat the same food, there is competition for a limited resource in the confined space

In reef ecosystems, corals often have microalgae living inside them. The algae supply the corals with nutrients, and the coral give shelter to the algae. Which of the following interactions best describes the relationship between the corals and the algae?

C) Mutualism

- The two organisms both benefit from the relationship

Which of the following best describes an example of resource partitioning in an ecosystem?

A) Two different bird species feed from the same oak tree; one eats acorns, and the other eats insects in the bark

- The two bird species are using the same resource in slightly different ways to reduce the negative impact of competition on the two species

Which of the following describes the most likely change to terrestrial biomes resulting from warmer average global temperatures?

A) The global distribution of midlatitude biomes, such as grasslands and temperate rain forests, would increase

- Warmer average global temperatures would expand the range of biomes currently found at midlatitudes

Which of the following terrestrial biomes has the highest net primary productivity?

B) Tropical rain forest

- Net primary productivity (NPP) is higher in biomes that are warm year-round and receive abundant rainfall and sunlight to encourage the growth of producers, which are all characteristics of tropical rain forests

Which of the following terrestrial biomes has the highest primary productivity per unit area?

B) Tropical rain forest

- Tropical rain forests have a yearlong growing season and more than 60 inches of rain per year. The warm climate and the rainfall leads to high levels of photosynthesis in the numerous plant species that inhabit the biome

This biome contains a nutrient-rich environment created by falling leaves and trapped organic materials from the large trees, and it provides the ecosystem service of filtering pollutants from water

B) Freshwater wetlands

- Freshwater wetlands have trees with roots that are submerged in water. The trees drop their leaves, and the water traps organic materials released from decomposition. The wetlands also trap pollutants

This biome is found in shallow waters off the coastline and is Earth's most biologically diverse marine biome

A) Coral reefs

- Corals live in vast colonies off the coast and create a reef that provides habitat for a variety of organisms, including algae, tropical fish, and birds

This freshwater biome is characterized by fast-flowing water that can originate from underground springs or runoff, which carries sediment and organic material

D) Rivers

- Rivers carry runoff from rain or snow. Turbulent water, known as rapids, form from the fast-moving water flow

Which of the following biogeochemical cycles includes the processes of buffering ocean pH and photosynthesis, as shown in the diagram?

A) The carbon cycle

- Carbon is converted from atmospheric CO2 to organic carbon compounds via photosynthesis, and carbon sequestered by the ocean buffers ocean pH

Which of the boxes represents a carbon source?

D) Burning of fossil fuels

- Burning fossil fuels is a source because it releases carbon that has been stored in coal, oil, or natural gas, which are carbon sinks

Which box represents a carbon sink that holds carbon compounds for the shortest period of time?

A) Vegetation

- Carbon dioxide can move into plants to be stored as glucose much more quickly than sedimentary rocks and fossil fuels can be stored. Carbon compounds are held for the shortest amount of time in vegetation

The diagram above best illustrates major processes in which of the following biogeochemical cycles?

C) The phosphorus cycle

- The phosphorus cycle does not have an atmospheric sink and is driven by weathering and uplift

Which of the following statements is best supported by the diagram of the phosphorus cycle?

B) The phosphates absorbed by animal tissue through consumption eventually return to the soil

- The phosphates absorbed by animal tissue through consumption eventually return to the soil through the excretion of plants and animals and their decomposition after death

Farmers in a suburban coastal town started using no-till agriculture, a practice that reduces soil erosion from their farmland. Use the image above to determine which of the following long-term effects no-till agriculture will have on the ecosystem surrounding the farmland

B) There will be less algal growth in the nearby ocean

- Phosphorous is a limiting factor in biological systems. By decreasing the amount of erosion, less phosphorous will run off into waterways and be available to algae to use for growth

Based on the diagram, which of the following statements about the hydrologic cycle is true?

A) Water from the ocean evaporates and condenses in the atmosphere

- The ocean is the largest reservoir and over 70% of the Earth's surface of water and therefore the greatest source for evaporation

The total rate of photosynthesis in a given area

B) Gross primary productivity

- Gross primary productivity is defined as the total rate of photosynthesis in a given area

This rate of reaction can be measured in the dark by determining the amount of oxygen gas consumed in a period of time

D) Cellular respiration

- Cellular respiration does not require sunlight, so it can be measured in the dark

The energy available to consumers determined by subtracting the energy used by plants from the total energy transformed by the process of photosynthesis

C) Net primary productivity

- Net primary productivity is the rate of energy storage by photosynthesizers after subtracting energy used for cellular respiration in plants

Which of the following best describes the flow of energy in most terrestrial and near-surface marine ecosystems?

D) Producers use energy from the sun to make organic matter, such as sugars, from carbon dioxide and water and are then consumed by organisms higher in the food chain

- Through the process of photosynthesis, plants convert solar energy into chemical energy, which moves through the food chain when one organism feeds on another

Which of the following best describes a terrestrial ecosystem that will have the highest net primary productivity?

A) Warm temperatures, high rainfall, and consistent sunlight

- Net primary productivity is highest in areas where temperatures are warm and water and solar energy are abundant and encourage the growth of producers

Which of the following trophic levels represents a primary producer in an aquatic food chain?

A) Phytoplankton

- Phytoplankton uses solar energy to produce food; it is a producer

A temperate grassland biome has a gross primary productivity of

3,480kilocalories/meter2/year and a net primary productivity of

2,000kilocalories/meter2/year. Which of the following is the approximate number of kilocalories/meter2/year available to herbivores in that biome?

A) 200 kilocalories/meter2/year

- 10% of the kilocalories from net primary productivity would be available (2,000kilocalories/meter2/year×0.10=200kilocalories/meter2/year x 0.10 = 200 kilocalories/meter2/year)

Energy is transferred along food chains from one stage to the next. Which statement best explains how the energy is transferred?

B) If a primary producer stores 10,000kcal of energy, then a tertiary consumer will have 10kcal of energy available

- Energy lost is 90% per trophic level so 10% is transferred. If level 1 (primary producer) stores 10,000kcal of energy, than level 2 (primary consumer) would have 1,000kcal of energy available, level 3 (secondary consumer) would have 100kcal of energy available, and level 4 (tertiary consumer) would have 10kcal of energy available (10,000kcal×0.10×0.10×0.10=10kcal)

Based on the food web shown above, which of the following correctly describes the flow of energy through the trophic levels from producers to quaternary consumers?

C) Brittlebrush, grasshopper, grasshopper mouse, rattlesnake, red-tailed hawk

- The energy flows up the food web through trophic levels based on feeding relationships

The largest area of old-growth forest in the United States is located in

A) Alaska

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

C) Tropical rainforest

- Tropical rain forest has a net primary productivity of about 2000 g C/m2/year. Net primary productivity is highest where temperatures are consistently warm, water is abundant, and day length is consistent all year. The tropical latitudes meet these conditions better than the latitudes of the other biomes

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

D) Tundra

- The underlying subsoil of tundra is permafrost, an impermeable, permanently frozen layer that prevents water from draining through it and roots from penetrating it. The tundra also receives less than 4 inches

of precipitation per year

The thick forest of this biome tends to be well adapted to short growing seasons

B) Taiga

- Taiga forests are located primarily between 50° and 60° N and are dominated by coniferous trees that are well adapted to the relatively short growing season of these latitudes

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

D) an increase in both mean annual temperature and mean annual precipitation

Which of the following best illustrates an abiotic component of the environment affecting a biotic component of the environment?

D) Low phosphorus content in soil limits the growth of vegetation.

The great grasslands of the world have which of the following primary characteristics in common?

D) Seasonal cycles of temperature and precipitation produce abundant vegetative growth

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

C) Their soils are relatively poor in nutrients

Which environment is most likely to be characterized by dry scrub with frequent fires?

C) graph - low precipitation and high temperature

Which environment is characterized by the highest diversity of tree species?

B) graph - high precipitation and steady temperature

The graph below shows the results obtained when two species of Paramecium were grown together in the same medium.

The graph above best exemplifies

D) competitive exclusion

In a typical forest ecosystem, dead trees and fallen trees are most important because of their role in which of the following?

B) Providing habitats for wildlife

Which of the following best describes the change in the elk population since the introduction of wolves into Yellowstone in 1995?

B) The elk population steadily decreased in numbers

- After the introduction of wolves into Yellowstone, the overall population size of the northern range elk began decreasing. In 1995 there were about 12,000 elk in the northern range population and 4,000 at the end of the data collection

Which of the following is a potential disadvantage of reintroducing wolves to Yellowstone?

B) Wolves leaving the park may prey on livestock in grazing land outside the park

- There are no controls preventing wolves from leaving the park and they could prey on livestock they come into contact with outside of the park boundaries

Based upon the data presented in the graph, which of the following best identifies the highest wolf population size?

C) 170

- Based on the data, the peak wolf population occurred between 2002 and 2005 and was between 170 and 175 wolves

Location 1 is most likely located in which of the following terrestrial biomes?

C) Tropical rain forest

- Tropical rain forests are characterized by consistently high solar radiation and temperature all year long

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

A) Greater accumulation of chapparal biomass

Based on the table, which of the following claims about the relationship between the tree finch and the invasive fly is best supported?

C) The flies and finches have a parasitic relationship; the finches provide a home for the fly, and the fly decreases the breeding success of the finches

- The data support a parasitic relationship. Parasitism is an interaction where one species lives on or in another species in a way that negatively affects the host species. The data demonstrate that the presence of the invasive fly lowers the percentage of successful matings in the finches, which harms the species

This biome is characterized by long dry seasons and is dominated by grasses, shrubs, and grazing animals

A) Savanna

- The savanna has long dry seasons, with grazing animals and fire that prevent the growth of many woody plants

Which of the following world regions contain the greatest area of rain forest?

E) Brazil and Indonesia

Which of the following best describes soil in many tropical rain forests?

B) They are quickly depleted nutrients when the forest is removed

Which of the following best describes a symbiotic relationship?

B) Intestinal bacteria inhabit the gut of humans

- Symbiosis is a close, extended relationship between two organisms of different species that benefits at least one member. Both humans and bacteria benefit from this relationship

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

C) Tropical rain forest

- Tropical rain forests are found along the equator, where the oceans provide a constant source of water vapor, leading to warm and wet conditions

The location of the greatest remaining natural biodiversity

E) South America

Which of the following best describes the movement of energy in an ecosystem?

B) Energy is harnessed by producers, and available energy decreases with each trophic level transfer

- Energy is harnessed from the sun by producers and is passed through trophic levels. The second law of thermodynamics explains how 90% of energy is lost between trophic levels

The table above shows the balanced chemical equations that represent three processes that are part of the nitrogen cycle. Which of the following is exemplified by the equations above?

C) Each biogeochemical cycle demonstrates the conservation of matter

- Each equation is balanced, demonstrating the conservation of matter in a biogeochemical cycle

Which of the following best explains why terrestrial trophic pyramids usually do not have levels higher than tertiary consumers?

C) 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

- As energy is transferred through trophic levels about 90% of the energy is lost to the environment as heat and thus there is not enough energy to support consumers past a third level, especially in terrestrial ecosystems

The total fertility rate in country A was 6.8 in 1980. Which of the following statements best supports the change in the total fertility rate in country A between 1980 and 2015?

C) The total fertility rate decreased as a result of a delay in age of first marriage and increased contraceptive use

- In developing countries, behavioral changes such as delayed first marriage and increased contraceptive use can lead to a decrease in total fertility rate

Which of the following countries has achieved replacement-level fertility?

C) Country C

- Replacement-level fertility is 2.1. Country C has a total fertility rate (TFR) of 2.1

Which of the following statements best describes the trends in the data shown in the graph above?

C) More-developed countries tend to have lower total fertility rates than less-developed countries

- The number of children per woman decreases in more-developed countries as result of education, women's rights, and economic empowerment of women

Which of the following is the best explanation for why there is such a small amount of phosphorus that moves into aquatic systems?

C) There is not a gaseous phase of the phosphorus cycle, and therefore the movement of phosphorus into oceanic reservoirs is very slow

- Phosphorus does not have a gaseous phase, so there is very little movement from the atmosphere. Most phosphorus must be transported via runoff

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?

D) Readily available organic phosphorus in the soil is assimilated by plants

- Phosphorus released into the ground by living organisms will be readily available for assimilation by producers

Based on the diagram, which of the following reservoirs contains the most phosphorus?

B) Sediments

- The primary reservoirs of phosphorus are rocks and sediments

Which of the following pathways indicate how nitrogen is added to the largest nitrogen reservoir?

C) Denitrifying bacteria and volcanic activity

- The atmosphere is the major reservoir of nitrogen. About 78 percent of our atmosphere is composed of nitrogen gas. Denitrifying bacteria and volcanic activity release nitrogen gas

In the nitrogen cycle illustrated above, nitrification occurs in which of the following steps?

C) Step 3

- Nitrification is the production of nitrates and nitrites by various species of bacteria

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

B) Phosphorus and nitrogen are both required for plant growth

- Nitrogen and phosphorus are both nutrients required for plant growth

How does the burning of fossil fuels contribute to the net increase in atmospheric carbon?

C) Carbon that has been sequestered underground is added to the carbon cycling between the atmosphere and the biosphere

Which of the following is a process that indirectly removes carbon from Earth's atmosphere?

A) Formation of carbonate deposits

Which of the following major storage reservoirs of carbon, stored in the form of carbon dioxide, is not represented in this diagram?

D) Ocean

- Carbon dioxide from the atmosphere dissolves in the surface waters of the ocean; the ocean stores large amounts of carbon dioxide

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

- Impervious materials directly decrease the amount of water infiltration and increase the amount of runoff

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?

C) 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?

C) Carbon sinks include forests and oceans.

Which of the following is an example of a carbon sink?

A) Deposition of organic matter on the deep ocean floor

Based on the diagram above, which of the following processes reduces the amount of carbon dioxide in the atmosphere?

A) Photosynthesis

- During photosynthesis, primary producers use carbon dioxide in the atmosphere as the carbon source to produce organic carbon compounds

Based on the diagram above, which process most directly results in the storage of carbon as coal and oil over millions of years?

C) Decomposition

- Decomposition of producers and consumers has led to the storage of carbon over millions of years. In the cycle presented, decomposition is the most direct cause of this storage

Directions: Select the choice that best fits each statement. The following question(s) refer to the following processes.

(A) Nitrification

(B) Denitrification

(C) Assimilation

(D) Ammonification

(E) Nitrogen fixation

Nitrate ions and nitrite ions are converted into nitrous oxide gas and nitrogen gas (N2)

B) Denitrification

Directions: Select the choice that best fits each statement. The following question(s) refer to the following processes.

(A) Nitrification

(B) Denitrification

(C) Assimilation

(D) Ammonification

(E) Nitrogen fixation

Ammonia is converted to nitrite, then to nitrate

A) Nitrification

Directions: Select the choice that best fits each statement. The following question(s) refer to the following processes.

(A) Nitrification

(B) Denitrification

(C) Assimilation

(D) Ammonification

(E) Nitrogen fixation

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

C) Assimilation

The diagrams above show an area that was once a pasture that has since undergone changes to the vegetation over time. 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?

A) Increased infiltration

- Vegetation, such as trees and shrubs, increases infiltration by increasing the time of water penetration in the soil

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 is powered by the Sun, is the movement of water from a liquid phase to a gaseous phase.

The greatest amount of fresh water is found in which of the following?

E) Polar ice caps and glaciers

According to the graph, the increase in CO2 concentration, in parts per million, between 1970 and 1990 is closest to

B) 30 ppm

Which of the following is most likely a significant cause of the general trend indicated by the graph?

E) Increase in consumption of fossil fuels

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

D) Nitrogen in the atmosphere, sulfur in the rocks

Directions: Select the choice that best fits each statement. The following questions(s) refer to the following elements.

(A) Carbon

(B) Sodium

(C) Sulfur

(D) Phosphorus

(E) Potassium

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

A) Carbon

Which of the following diagrams correctly illustrates the nitrogen cycle?

A) graph with N2 on both sides of tree

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?

D) Readily available organic phosphorus in the soil is assimilated by plants

- Phosphorus released into the ground by living organisms will be readily available for assimilation by producers

Based on the diagram, which of the following reservoirs contains the most phosphorus?

B) Sediments

- The primary reservoirs of phosphorus are rocks and sediments

The two major processes involved in the carbon cycle are

B) Photosynthesis and respiration

Photosynthesis is the major source of which of the following gases in Earth's atmosphere?

C) O2

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

B) Transpiration

Approximately what percent of the water on Earth is freshwater (liquid and solid)?

C) 2.5%

The cities of Edmonton and Calgary are relatively far north and at high elevation. Which of the following best explains the data presented in their ecological footprints?

D) Colder average temperatures and longer nights in Edmonton and Calgary lead to high energy usage to heat and light homes

- The primary difference in the footprints of these cities is housing, which is related to the energy needed to heat and provide lighting during the winter

Eutrophication results in the death of trout and other fish as a result of

B) Asphyxiation from lack of oxygen

Why did the DO after one week decrease as the amount of waste increased?

C) The algae multiplied and then died and decomposed

What is the main purpose for the experiment?

E) To observe the effect of organic waste on DO

Which of the following would best improve the validity of the experiment?

C) Repeating the experiment several times and comparing the results