Practice Quiz #8 - BIO 212
Burning fossil fuels releases oxides of sulfur and nitrogen. These air pollutants can be responsible for ________. a. precipitation with a pH as high as 8.0 b. eutrophication of lakes c. the death of fish in lakes d. global temperature decrease
c. the death of fish in lakes
What is the biological significance of genetic diversity between populations? a. Genetic diversity reduces the probability of extinction. b. The population that is most fit would survive by competitive exclusion. c. Genes for traits conferring an advantage to local conditions are unlikely. d. Diseases and parasites are not spread between separated populations.
a. Genetic diversity reduces the probability of extinction.
Use the following figure to answer the question. On the diagram of the nitrogen cycle, which number represents nitrite (NO2)? a. 3 b. 4 c. 1 d. 2
a. 3
Owls eat rats, mice, shrews, and small birds. Assume that, over a period of time, an owl consumes 5,000 J of animal material. The owl loses 2,300 J in feces and owl pellets and uses 2,500 J for cellular respiration. What is the production efficiency of this owl? a. 7.4% b. 40% c. 2% d. 8%
a. 7.4%
The Hubbard Brook watershed deforestation experiment yielded all of the following results except which of the following? a. Calcium levels remained high in the soil of deforested areas. b. Deforestation increased water runoff. c. Most minerals were recycled within a forest ecosystem. d. The nitrate concentration in waters draining the deforested area became dangerously high.
a. Calcium levels remained high in the soil of deforested areas.
Suppose you are studying the nitrogen cycling between vegetation, sediments, and water in a pond ecosystem over the course of a month. While you are collecting data, a flock of 100 Canada geese lands and spends the night during a fall migration. What could you do to eliminate error in your study as a result of this event? a. Find out how much nitrogen is consumed from vegetation and eliminated by a Canada goose over about a 12-hour period and multiply this number by 100; enter this +/- value into the nitrogen budget of the ecosystem. b. Find out how much nitrogen is consumed in plant material by a Canada goose over about a 12-hour period, multiply this number by 100, and add that amount to the total nitrogen in the ecosystem. c. Put a net over the pond so that no more migrating flocks can land on the pond and alter the nitrogen balance of the pond. d. Find out how much nitrogen is eliminated by a Canada goose over about a 12-hour period, multiply this number by 100, and subtract that amount from the total nitrogen in the ecosystem.
a. Find out how much nitrogen is consumed from vegetation and eliminated by a Canada goose over about a 12-hour period and multiply this number by 100; enter this +/- value into the nitrogen budget of the ecosystem.
Which of the following statements about protected areas that have been established to preserve biodiversity is correct? a. Management of a protected area should be coordinated with management of the land surrounding the area. b. Developing nations have a larger ecological footprint than developed nations, thus protected areas should be primarily established in developing nations. c. About 25 percent of Earth's land area is now protected. d. It is only important to protect land within biodiversity hot spots.
a. Management of a protected area should be coordinated with management of the land surrounding the area.
Loss of biodiversity matters not only with regard to mammals or other vertebrates, but also microbes. Why are microbes worthy of discovery and protection from extinction? a. Microbes may produce unique proteins useful in genetic research. b. Microbes play a role in digestion. c. Microbes may be the most sensitive to the next large extinction event. d. Microbes are much greater in species number than any other taxa on Earth.
a. Microbes may produce unique proteins useful in genetic research.
Why is it that satellites, using wavelength reflectance technology, detect variable levels of productivity across Earth's oceans, rather than an increase toward the equator? a. NPP in Earth's open oceans could differ due to variability in depth, the presence of coral reefs, or by ocean currents. b. Satellites detect differences by measuring the amount of water vapor emitted by transpiring producers, and this is a variable measurement in the oceans. c. Light at the equator is too constant and direct. d. Temperatures at the equator often exceed those which are optimal for primary production.
a. NPP in Earth's open oceans could differ due to variability in depth, the presence of coral reefs, or by ocean currents.
Use the following figure to answer the question. Examine the figure, which notes the average barrels of oil used per person per year in different countries. What can be concluded? a. Residents of more affluent, industrialized countries use more energy per person. b. Residents in warmer climates use more energy per person. c. English-speaking countries tend to use more energy per person. d. Residents of more populated countries use more energy per person.
a. Residents of more affluent, industrialized countries use more energy per person.
What is the single greatest threat to biodiversity? a. habitat alteration, fragmentation, and destruction b. overharvesting of commercially important species c. novel pathogens d. introduced species that compete with native species
a. habitat alteration, fragmentation, and destruction
The human impact that scientists determined has caused the most extinctions on record is ________, and beyond further losses from this impact, the other impact with the largest potential to cause future extinctions is ________. a. habitat loss; climate change b. climate change; habitat loss c. habitat loss; overharvesting d. introduced species; habitat loss
a. habitat loss; climate change
What strategy was used to rescue Illinois prairie chickens from a recent extinction vortex? a. introducing individuals from other populations to increase genetic variation b. establishing a nature reserve to protect its habitat nesting grounds c. reducing the population size of its predators and competitors d. determining the minimum viable population size by taking into account the effective population size
a. introducing individuals from other populations to increase genetic variation
Use the following figure to answer the question. Consider the global nitrogen cycle depicted in the figure. What is the limiting portion of the cycle for plants? a. nitrogen fixation by bacteria b. nitrogen lost to the atmospheres c. industrial nitrogen fixation d. internal nitrogen cycling in the oceans
a. nitrogen fixation by bacteria
Use the following figure (on doc) to answer the question. Examine the figure and consider this hypothesis: Plant biomass increases with species richness. Functional groups are categories of plants each containing numerous species, such as grasses and wildflowers, or trees and shrubs. In looking at the data in the figure, how would you relate it to this hypothesis? The hypothesis is ________. a. partially supported b. neither rejected nor supported c. supported d. rejected
a. partially supported
The first step in ecosystem restoration is to ________. a. restore the physical structure b. remove competitive invasive species c. remove toxic pollutants d. restore native species that have been extirpated due to disturbance
a. restore the physical structure
Movement corridors can be harmful to certain species because they ________. a. spread disease and parasites b. increase genetic diversity c. allow seasonal migration d. increase inbreeding
a. spread disease and parasites
What is a critical load? a. the amount of added nutrient that can be absorbed by plants without damaging ecosystem integrity b. the level of a given toxin in an ecosystem that is lethal to 50 percent of the species present c. the amount of nutrient augmentation necessary to bring a depleted habitat back to its former level d. the number of predators an ecosystem can support that effectively culls prey populations to healthy levels
a. the amount of added nutrient that can be absorbed by plants without damaging ecosystem integrity
Which of the following has the greatest effect on the rate of chemical cycling within an Ecosystem? a. the rate of decomposition in the ecosystem b. the trophic efficiency of the ecosystem c. the secondary production efficiency of the ecosystem's consumers d. the ecosystem's rate of primary production
a. the rate of decomposition in the ecosystem
Consider the food chain of grass → grasshopper → mouse → snake → hawk. About how much of the chemical energy fixed by photosynthesis of the grass (100 percent) is available to the hawk? a. 1% b. 0.01% c. 0.1% d. 10%
b. 0.01%
Use the following figure (on doc) to answer the question. According to the figure, which two consecutive years had the largest change in the population growth rate? a. 1922-1923 b. 1938-1939 c. 1985-1986 d. 1967-1968
b. 1938-1939
Use the following figure (on doc) to answer the question. Looking at the figure, what can you conclude about the data? a. As species richness decreases, plant biomass increases. b. As species richness increases, plant biomass increases and then levels off. c. As species richness changes, plant biomass remains consistent. d. As species richness increases, plant biomass increases.
b. As species richness increases, plant biomass increases and then levels off.
If you applied a fungicide to a cornfield, what would you expect to happen to the rate of decomposition and net ecosystem production (NEP)? a. Both decomposition rate and NEP would decrease. b. Decomposition rate would decrease and NEP would increase. c. Neither would change. d. Decomposition rate would increase and NEP would decrease.
b. Decomposition rate would decrease and NEP would increase.
Use the following figure to answer the question. Food web for a particular terrestrial ecosystem (arrows represent energy flow and letters represent species). Examine this food web for a particular terrestrial ecosystem. Which species is most likely a decomposer on this food web? a. A b. E c. C d. B
b. E
Why does a vegetarian leave a smaller ecological footprint than an omnivore? a. Fewer animals are slaughtered for human consumption. b. Eating meat is an inefficient way of acquiring photosynthetic productivity. c. Vegetarians need to ingest less chemical energy than omnivores. d. There is an excess of plant biomass in all terrestrial ecosystems.
b. Eating meat is an inefficient way of acquiring photosynthetic productivity.
Ecosystem services include processes that increase the quality of the abiotic environment. Which of the following processes would fall under this category? a. Bees, flies, and wasps pollinate many plants. b. Green plants and phytoplankton produce the oxygen we breathe. c. Keystone predators have a marked effect on species diversity. d. The presence of dams improves flood control.
b. Green plants and phytoplankton produce the oxygen we breathe.
Why are changes in the global carbon cycle important? a. Deforestation and suburbanization increase an area's net primary productivity. b. Increasing atmospheric concentrations of carbon dioxide are altering Earth's climate. c. Burning increases available carbon for primary producers and, therefore, primary consumers. d. By using fossil fuels, we are replenishing a nonrenewable resource
b. Increasing atmospheric concentrations of carbon dioxide are altering Earth's climate.
Matter may be gained by, or lost from, ecosystems. How does this occur? a. Photosynthetic organisms convert solar energy to sugars. b. Matter can move from one ecosystem to another. c. Chemoautotrophic organisms can convert matter to energy. d. Heterotrophs convert heat to energy.
b. Matter can move from one ecosystem to another.
Why do logged tropical rain forest soils typically have nutrient-poor soils? a. Logging results in soil temperatures that are lethal to nitrogen-fixing bacteria. b. Most of the nutrients in the ecosystem are removed in the harvested timber. c. The cation exchange capacity of the soil is reversed as a result of logging. d. Tropical bedrock contains little phosphorous.
b. Most of the nutrients in the ecosystem are removed in the harvested timber.
Which of the following is an accurate statement regarding mineral nutrients in soils and their implication for primary productivity? a. Globally, phosphorous availability is most limiting to primary productivity. b. Phosphorous is sometimes unavailable to producers due to leaching. c. Alkaline soils are more productive than acidic soils. d. Adding a nonlimiting nutrient will stimulate primary productivity.
b. Phosphorous is sometimes unavailable to producers due to leaching.
Your friend is wary of environmentalists' claims that global warming could lead to major biological change on Earth. Which of the following statements can you use in response to your friend's suspicions? a. Through measurements and observations, we know that carbon dioxide levels and temperature fluctuations are indirectly correlated. b. Scientist have evidence that climate change has already altered primary production, as well as ecosystem services. c. We know that atmospheric carbon dioxide has decreased over the past 150 years. d. Global warming could have minor effects on agriculture in the United States.
b. Scientist have evidence that climate change has already altered primary production, as well as ecosystem services.
Tropical forests are being converted to farm or pasture land at an alarming rate, and one major focus is on the biodiversity and the impact to these ecosystems. What is a direct benefit to humans that helps explain why these forests need to be preserved? a. The plant diversity provides shade, which lowers global warming. b. The diversity could contain novel drugs for consumers. c. This diversity provides areas for coffee growing. d. Natural and undisturbed areas are important wildlife habitats.
b. The diversity could contain novel drugs for consumers.
Use the following figure to answer the question. Five new individuals were added to a small population of bighorn sheep in 1986, and ten more were added between 1990 and 1994. According to the figure, what occurred in this population after these additions? a. The population increased exponentially. b. The population growth rate increased. c. The population continued to decline. d. The population increased in overall numbers.
b. The population growth rate increased.
Which of the following statements regarding extinction is accurate? a. A large percentage of species are immune from extinction; however, rates of extinction may increase with continued human impacts. b. The small-population approach is inferior to the declining-population approach if the goal is to conserve the maximum number of species in a given region. c. Extinctions occur only periodically, separated by long time spans with no extinctions. d. Extinction is occurring at a similar rate now as compared to historical fossil evidence.
b. The small-population approach is inferior to the declining-population approach if the goal is to conserve the maximum number of species in a given region.
Which of the following would be considered an example of bioremediation? a. using a bulldozer to regrade a strip mine b. adding seeds of a chromium-accumulating plant to soil contaminated by chromium c. adding nitrogen-fixing microorganisms to a degraded ecosystem to increase nitrogen availability d. reconfiguring the channel of a river
b. adding seeds of a chromium-accumulating plant to soil contaminated by chromium
Which of these ecosystems has the lowest net primary production per square meter? a. a salt marsh b. an open ocean c. a coral reef d. a tropical rain forest
b. an open ocean
For most terrestrial ecosystems, pyramids composed of species abundances, biomass, and energy are similar in that they have a broad base and a narrow top. The primary reason for this pattern is that ________. a. biomagnification of toxic materials limits the secondary consumers and top carnivores b. at each step, energy is lost from the system c. top carnivores and secondary consumers have a more general diet than primary producers d. secondary consumers and top carnivores require less energy than producers
b. at each step, energy is lost from the system
Introduced species can have deleterious effects on biological communities by ________. a. reducing erosion b. competing with native species for resources and displacing them c. increasing the biodiversity in their new region d. spreading rapidly in their new region
b. competing with native species for resources and displacing them
If the sun were to suddenly stop providing energy to Earth, most ecosystems would eventually vanish. Which of the following ecosystems would likely survive the longest after this hypothetical disaster? a. a desert spring b. deep benthic ocean c. pelagic ocean d. tundra
b. deep benthic ocean
If all individuals in the last remaining population of a particular frog species were all highly related, which type of diversity would be of greatest concern when planning to prevent the species from going extinct? a. ecosystem diversity b. genetic diversity c. global diversity d. local diversity
b. genetic diversity
Which of the following observations provides the best evidence of a biodiversity crisis? a. increasing pollution levels b. high rate of extinction c. climate change d. the incursion of a non-native species
b. high rate of extinction
Use the following figure to answer the question. Consider the global nitrogen cycle depicted in the figure. How are humans altering this cycle? a. reduction of nitrogen available to terrestrial ecosystems b. industrial nitrogen fixation c. reduction of nitrogen fixation by bacteria d. nitrogen lost to the atmosphere
b. industrial nitrogen fixation
During the inventory of bacterial genes present in the Sargasso Sea, a deep isolated area in the middle of the Atlantic Ocean, a research team concluded that at least 1,800 bacterial species were present. Based on what you might predict about the habitat structure of such an area, what kind of bacterial diversity would you expect to see in tropical coral reef waters? a. slightly smaller genetic diversity b. markedly greater genetic diversity c. slightly greater genetic diversity d. markedly smaller genetic diversity
b. markedly greater genetic diversity
The Hubbard Brook watershed deforestation experiment revealed that ________. I) deforestation increased water runoff II) nitrate concentration in waters draining the deforested area became dangerously high III) calcium levels remained high in the soil of deforested areas a. only II b. only I and II c. only I d. only III
b. only I and II
Use the following figure (on doc) to answer the question. Which habitat type in the figure makes available the most new tissue to consumers? a. tropical wet forest b. open ocean c. algal beds and reefs d. wetlands
b. open ocean
Brown-headed cowbirds utilize fragmented forests effectively by ________. a. consuming the eggs of other species as well as insects and seeds in open fields b. parasitizing the nests of forest birds and feeding on open-field insects c. feeding on the fruits of shrubs that tend to grow at the forest/open-field interface d. outcompeting other songbird species for access to nesting holes in old-growth trees
b. parasitizing the nests of forest birds and feeding on open-field insects
Which of the following organisms is correctly paired with its trophic level? a. grasshopper—secondary consumer b. phytoplankton—primary producer c. fungus—primary consumer d. cyanobacterium—primary consumer
b. phytoplankton—primary producer
The discipline that applies ecological principles to returning degraded ecosystems to a more natural state is known as ________. a. conservation ecology b. restoration ecology c. landscape ecology d. resource conservation
b. restoration ecology
Which trophic level is most vulnerable to extinction? a. secondary consumer level b. tertiary consumer level c. primary consumer level d. producer level
b. tertiary consumer level
The main cause of the increase in the amount of CO2 in Earth's atmosphere over the past 150 years is... a. increased worldwide primary production. b. the burning of larger amounts of wood and fossil fuels. c. increased worldwide standing crop. d. an increase in the amount of infrared radiation absorbed by the atmosphere.
b. the burning of larger amounts of wood and fossil fuels.
Agricultural lands frequently require nutrient augmentation because ________. a. land that is available for agriculture tends to be nutrient-poor b. the nutrients that become the biomass of plants are not cycled back to the soil on lands where they are harvested c. cultivation of agricultural land inhibits the decomposition of organic matter d. nitrogen-fixing bacteria are not as plentiful in agricultural soils because of the use of pesticides
b. the nutrients that become the biomass of plants are not cycled back to the soil on lands where they are harvested
Which of the following locations are major reservoirs for carbon in the carbon cycle? a. fossilized plant and animal remains (coal, oil, and natural gas) b. the ocean, atmosphere, and fossilized and live plant and animal biomass c. the atmosphere d. sediments and sedimentary rocks
b. the ocean, atmosphere, and fossilized and live plant and animal biomass
The main goal of sustainable development is to ________. a. reevaluate and re-implement management plans over time b. use natural resources such that they do not decline over time c. involve more countries in conservation efforts d. use only natural resources in the construction of new buildings
b. use natural resources such that they do not decline over time
Of the following ecosystem types, which have been impacted the most by humans? a. desert and high alpine b. wetland and riparian c. tundra and arctic d. taiga and second-growth forests
b. wetland and riparian
Which of the following organisms is incorrectly paired with its trophic level? a. cyanobacterium—primary producer b. zooplankton—primary producer c. fungus—detritivore d. grasshopper—primary consumer
b. zooplankton—primary producer
Use the following figure to answer the question. Based on the species-area plot in the figure, if habitable area on an island were reduced from 10,000 square kilometers (km2) to 1,000 km2, roughly what percentage of the species would disappear? a. 0.3 percent b. 3 percent c. 30 percent d. 60 percent
c. 30 percent
Use the following figure to answer the question. On the diagram of the nitrogen cycle, which number represents the ammonium ion (NH4+)? a. 3 b. 2 c. 4 d. 1
c. 4
Of the following statements about protected areas that have been established to preserve biodiversity, which one is not correct? a. National parks are one of many types of protected areas. b. Management of a protected area should be coordinated with management of the land surrounding the area. c. About 25% of Earth's land area is now protected. d. It is especially important to protect biodiversity hot spots.
c. About 25% of Earth's land area is now protected.
Use the following figure (on doc) to answer the question. Looking at the figure showing the results of forest fragmentation, what can be said about edge effects? a. Species diversity decreases along the edges of forest fragments. b. Fragmentation does not affect biomass. c. Biomass declines along edges of forest fragments. d. Biomass increases along the edges of forest fragments
c. Biomass declines along edges of forest fragments.
Which one of the following is most likely to be a hot spot of biodiversity for birds? a. Central Australia b. Northern Europe c. Central America d. Eastern North America
c. Central America
Eutrophication is often caused by excess limiting-nutrient runoff from agricultural fields into aquatic ecosystems. This process results in massive algal blooms that eventually die and decompose, ultimately depleting the dissolved oxygen, killing large numbers of fish and other aquatic organisms. Predict which of the following human actions would best address the problem of eutrophication near agricultural areas? a. After each eutrophication event, remove the dead fish and invertebrates to place on agricultural fields instead of fertilizer. b. Remove the algae before it dies and decomposes to prevent eutrophication from occurring. c. Determine critical nutrient loads required for certain crops, and do not exceed this amount during fertilizer application. d. Determine which limiting nutrient is responsible for the algal bloom, and use other fertilizers to apply to crops.
c. Determine critical nutrient loads required for certain crops, and do not exceed this amount during fertilizer application.
If the flow of energy in an arctic ecosystem goes through a simple food chain, perhaps involving humans, starting from phytoplankton to zooplankton to fish to seals to polar bears, then which of the following could be accurate? a. Polar bears can provide more food for humans than seals can. b. The total biomass of the fish is lower than that of the seals. c. Fish can potentially provide more food for humans than seal meat. d. Seal populations are larger than fish populations.
c. Fish can potentially provide more food for humans than seal meat.
Which of the following strategies would most rapidly increase the genetic diversity of a population in an extinction vortex? a. Control populations of the endangered population's predators and competitors. b. Establish a reserve that protects the population's habitat. c. Introduce new individuals transported from other populations of the same species. d. Sterilize the least fit individuals in the population.
c. Introduce new individuals transported from other populations of the same species.
The goal of restoration ecology is to ________. a. manage competition among species in human-altered ecosystems b. replace a ruined ecosystem with a more suitable ecosystem for that area c. return degraded ecosystems to a more natural state d. prevent further degradation by protecting an area with park status
c. return degraded ecosystems to a more natural state
During a year, plants never use 100% of the incoming solar radiation for photosynthesis. What is a reasonable explanation for this? a. The pigments that drive photosynthesis absorb all of the wavelengths of light that are available; however, some of the light is subsequently reflected. b. Plants cannot photosynthesize as well in warm temperatures as in cold temperatures. c. Plants do not intercept all incoming light, as some light will strike water, bare soil, or rock. d. At least 75% of all incoming light is reflected, absorbed, or scattered back by clouds in the atmosphere.
c. Plants do not intercept all incoming light, as some light will strike water, bare soil, or rock.
Why is terrestrial productivity higher in equatorial climates? a. Productivity increases with temperature. b. Productivity increases with water availability. c. The answer is most likely a combination of the other responses. d. Productivity increases with available sunlight.
c. The answer is most likely a combination of the other responses.
Which of the following statements is accurate with respect to the red-cockaded woodpecker populations in the southeastern United States? a. All of the appropriate red-cockaded woodpecker habitats have already been logged or converted to agricultural land. b. The mature pine forests in which they live should continue to be protected from forest fire. c. The bird requires feeding grounds in and around mature pine forest that are uninterrupted by the structure of other vegetation. d. The red-cockaded woodpecker relies on dense forest to hide their nests from ground-dwelling predators.
c. The bird requires feeding grounds in and around mature pine forest that are uninterrupted by the structure of other vegetation.
Suppose you attend a town meeting at which some experts tell the audience that they have performed a cost-benefit analysis of a proposed transit system that would probably reduce overall air pollution and fossil fuel consumption. The analysis, however, reveals that ticket prices will not cover the cost of operating the system when fuel, wages, and equipment are taken into account. As a biologist, you know that if ecosystem services had been included in the analysis, the experts might have arrived at a different answer. Why are ecosystem services rarely included in economic analyses? a. Federal laws of the United States exclude their inclusion in any cost benefit analysis. b. Ecosystem services only take into account abiotic factors that affect local environments. c. Their cost is difficult to estimate, and people take them for granted. d. They have a low value and are usually not cost effective.
c. Their cost is difficult to estimate, and people take them for granted.
Use the following figure (on doc) to answer the question. Which category in the figure makes available the highest productivity per square meter? a. tropical wet forest b. open ocean c. algal beds and reefs d. wetlands
c. algal beds and reefs
Which of the following factors could cause the largest increase in the effective population size of a species? a. an increase in the total population size b. an increased number of females c. an increase in the number of breeding males and females d. an increased number of males
c. an increase in the number of breeding males and females
The main purpose of movement corridors is to ________. a. slowly introduce a species to a new reserve b. slow down the introduction of new individuals of a species c. connect two otherwise isolated populations d. create more edge habitat
c. connect two otherwise isolated populations
Use the following figure to answer the question. In the figure, what could the jagged arrow leaving microorganisms and other detritivores represent? a. energy consumed by bacteria b. CO2 and heat loss from decomposing materials due to the effects of solar radiation and precipitation c. energy lost from a worm during cellular respiration d. organic compounds broken down by bacteria
c. energy lost from a worm during cellular respiration
Which of the following outcomes is caused by excessive nutrient runoff into aquatic ecosystems? a. biological magnification b. depletion of ozone layer c. eutrophication d. acid precipitation
c. eutrophication
Which of the following ecosystems would likely have the largest net primary productivity per hectare and why? a. deep ocean, due to the high activity of chemoautotrophs at deep sea vents b. open ocean, because of the total biomass of photosynthetic autotrophs c. grassland, because of rapid growth, the small standing crop biomass that results from consumption by herbivores, and rapid decomposition d. tundra, because of the incredibly rapid period of growth during the summer season
c. grassland, because of rapid growth, the small standing crop biomass that results from consumption by herbivores, and rapid decomposition
One characteristic that distinguishes a population in an extinction vortex from most other populations is that... a. it is a rare, top-level predator. b. it is not well adapted to edge conditions. c. its genetic diversity is very low. d. its effective population size is lower than its total population size.
c. its genetic diversity is very low.
Which one of the following correctly ranks these organisms in order from lowest to highest percent in production efficiency? a. fish, insects, mammals b. mammals, insects, fish c. mammals, fish, insects d. insects, fish, mammals
c. mammals, fish, insects
Use the following figure (on doc) to answer the question. Based on the figure, which of the following are plausible reasons for the results? I)Nutrients in the control watershed are being lost due to evapotranspiration from leaves. II)Nutrients dissolve in the water running through the watershed. III)Nutrients are attached to small particles of sand or clay that leave the watershed. IV)Intact vegetation includes plant roots that held soil particles and prevented nutrient loss. a. I, II, III, and IV b. only I and III c. only II, III, and IV d. only II and IV
c. only II, III, and IV
Which of the following threats to biodiversity is targeted at specific species rather than groups of species? a. introduced species b. habitat destruction c. overharvesting d. increased levels of atmospheric carbon dioxide, a cause of global warming
c. overharvesting
To recycle nutrients, an ecosystem must have, at a minimum, ________. a. producers, primary consumers, secondary consumers, and decomposers b. producers c. producers and decomposers d. producers, primary consumers, and decomposers
c. producers and decomposers
Which of the following has the greatest effect on the rate of chemical cycling in an ecosystem? a. the production efficiency of the ecosystem's consumers b. the trophic efficiency of the ecosystem c. the rate of decomposition in the ecosystem d. the location of the nutrient reservoirs in the ecosystem
c. the rate of decomposition in the ecosystem
Use the graphs to answer the question. Archeological, fossil, and geological data provide information on the Mayan populations and their environment in Mexico, in the Caribbean state of Yucatán. The graphs depict population size, percentage of the land that was forested, and the amount of soil erosion. Based on the figure, what can you conclude about the history of land use in the southern Yucatán? a. Reduction in forest cover caused the Mayan population to crash. b. This Mayan population practiced sustainable development. c. Massive soil erosion caused the Mayan population to crash. d. As Mayan population increased, deforestation increased, probably leading to increased soil erosion.
d. As Mayan population increased, deforestation increased, probably leading to increased soil erosion.
Which statement best describes what ultimately happens to the chemical energy that is consumed but not used to produce new biomass in the process of energy transfer between trophic levels in an ecosystem? a. Heat produced by cellular respiration is used by heterotrophs for thermoregulation. b. It is undigested and winds up in the feces and is not passed on to higher trophic levels. c. It is used by organisms to maintain their life processes through the reactions of cellular respiration. d. It is eliminated as feces or is dissipated into space as heat as a result of cellular respiration consistent with the second law of thermodynamics.
d. It is eliminated as feces or is dissipated into space as heat as a result of cellular respiration consistent with the second law of thermodynamics.
Erwin and Scott used an insecticidal fog to knock down insects from the top section of a L. seemannii tree. The researchers identified over 900 species of beetles among the individuals that fell. Erwin also projected that this entire tree from top to bottom is host to about 600 arthropod species that are unique to this tree species and not found on any other tree species. There are approximately 50,000 species of tropical trees. Although it could not be entirely accurate, what would be the best way to estimate the total number of arthropod species? a. Estimate the species density and then multiply by 50,000. b. Add 900 to 600, and then multiply by 50,000. c. Multiply 50,000 by 900. d. Multiply 600 by 50,000.
d. Multiply 600 by 50,000.
What advantage would there be for an ecosystem ecologist to measure net ecosystem production (NEP) instead of net primary production (NPP)? a. NEP can be expressed in terms of carbon fixed by photosynthesis for an entire ecosystem, minus respiration by producers, allowing the measurement of net CO2 flux. b. NPP cannot be expressed in energy/unit of area/unit of time. c. NPP shows the rate at which the standing crop is utilized by consumers. d. NEP represents the amount of energy from light converted to chemical energy, minus the energy used by all organisms for cellular respiration, which could indicate whether or not carbon is being stored.
d. NEP represents the amount of energy from light converted to chemical energy, minus the energy used by all organisms for cellular respiration, which could indicate whether or not carbon is being stored.
Use the following figure (on doc) to answer the question. After looking at the results in the figure, what can be concluded about productivity in the experimental ecosystem? a. Productivity at a depth of 30 m is low only because of a lack of sunlight, not a lack of iron sulfate. b. Productivity is higher at depth than at the surface, but only initially. c. Productivity is higher at the surface than at depth, and would be predicted to increase sharply after day 12. d. Productivity is higher at the surface than at depth; however, an additional experiment could further test the effect of depth by introducing FeSO4 at 30 m deep and measuring the chlorophyll a response.
d. Productivity is higher at the surface than at depth; however, an additional experiment could further test the effect of depth by introducing FeSO4 at 30 m deep and measuring the chlorophyll a response.
Easter Island is an extremely isolated island in the Pacific, about 3,500 km from South America. Although there are no forests on the island now, archeological studies, fossil pollen, and other data show that Easter Island was once home to forests containing giant palms and other trees. Some scientists think that the removal of the giant palms caused the forest ecosystem to collapse. Which of the following factors might have caused this collapse? a. Shade-tolerant species increased in diversity in the absence of the palm. b. Soil erosion decreased in the absence of the palm. c. Productivity increased, thereby increasing competition, in the palms' absence. d. The absence of the palm trees may have reduced habitat quality for many other species.
d. The absence of the palm trees may have reduced habitat quality for many other species.
Use the following figure to answer the question. In looking at the species-area plot in the figure, what can be concluded? a. Two island land areas do not correlate to the number of bird species b. Diversity is independent from island area. c. The number of bird species increases exponentially with island area. d. The number of bird species increases linearly with island area.
d. The number of bird species increases linearly with island area.
Which of the following statements is correct about biogeochemical cycling? a. The carbon cycle has maintained a constant atmospheric concentration of carbon dioxide for the past million years. b. Phosphorus is the limiting nutrient that most widely affects biomass production. c. The nitrogen cycle involves movement of diatomic nitrogen between the biotic and abiotic components of the ecosystem. d. The phosphorus cycle involves the weathering of rocks.
d. The phosphorus cycle involves the weathering of rocks.
A land developer and several ecologists are discussing how a parcel of private land should be developed with housing while saving 20 hectares as natural habitat. The land developer suggests that the 20 hectares be divided into 20 separate 1-hectare areas, spread out across the area. The ecologists suggest that it would be better to have one intact parcel of 20 hectares on one side of the larger area. What is the significance of these different arrangements of the 20 hectares? a. The separate 1-hectare plots are less vulnerable to edge effects. b. The isolated hectare plots increase the ability of individuals to disperse from one habitat to another. c. The large plot will create more inbreeding in many species. d. The single intact parcel would have a smaller amount of edge than the 20 separate parcels.
d. The single intact parcel would have a smaller amount of edge than the 20 separate parcels.
Which of the following is a consequence of biological magnification? a. Only a small portion of the energy captured by producers is transferred to consumers. b. Populations of top-level predators are generally smaller than populations of primary consumers. c. The biomass of producers in an ecosystem is generally higher than the biomass of primary consumers. d. Toxic chemicals in the environment pose greater risk to top-level predators than to primary consumers.
d. Toxic chemicals in the environment pose greater risk to top-level predators than to primary consumers.
Many of the organisms in the ocean are nutrient-limited. If you wanted to investigate this phenomenon, one reasonable approach would be to ________. a. observe Antarctic Ocean productivity from year to year to see if it changes b. compare nutrient concentrations between the photic zone and the benthic zone in various marine locations c. contrast nutrient uptake by autotrophs in marine locations that are different temperatures d. experimentally enrich some areas of the ocean and compare their productivity to that of untreated areas
d. experimentally enrich some areas of the ocean and compare their productivity to that of untreated areas
Which of the following terms encompasses all of the others? a. herbivores b. carnivores c. primary consumers d. heterotrophs
d. heterotrophs
Overharvesting encourages extinction and is most likely to affect ________. a. edge-adapted species b. animals that occupy a broad ecological niche c. most organisms that live in the oceans' coral reefs d. large animals with low intrinsic reproductive rates
d. large animals with low intrinsic reproductive rates
Use the following figure to answer the question. Diagram of a food web (arrows represent energy flow and letters represent species). If the figure represents a terrestrial food web, the combined biomass of C + D would probably be ________. a. greater than the biomass of B b. less than the biomass of E c. greater than the biomass of A d. less than the biomass of A + B
d. less than the biomass of A + B
Use the following figure (on doc) to answer the question. In the ecosystem figure, which unit of the food web has the potential to lose the most energy as heat? a. microorganisms and other detritivores b. primary consumers c. secondary and tertiary consumers d. primary producers
d. primary producers
Managing southeastern forests specifically for the red-cockaded woodpecker ________. a. focused on the removal of standing dead longleaf pine to promote growth of young longleaf pine b. required the construction of nest boxes in the forest to promote successful nesting c. contributed to greater abundance and diversity of other forest plant species d. required periodic forest burning to reduce the growth of a dense understory of trees and shrubs
d. required periodic forest burning to reduce the growth of a dense understory of trees and shrubs
The primary difference between the small-population approach and the declining-population approach to biodiversity recovery is that ________. a. small-population approach would investigate and eliminate all of the human impacts on the habitat of the species being studied for recovery b. declining-population approach would likely involve bringing together individuals from scattered small populations to interbreed in order to promote genetic diversity c. small-population approach applies for conservation biologists when population numbers fall below 500 d. small-population approach is interested in bolstering the genetic diversity of a threatened population rather than the environmental factors that caused the population's decline
d. small-population approach is interested in bolstering the genetic diversity of a threatened population rather than the environmental factors that caused the population's decline