Ecology

The symbols +, -, and o are to be used to show the results of interactions between individuals and groups of individuals in the examples that follow. The symbol + denotes a positive interaction, — denotes a negative interaction, and o denotes where individuals are not affected by interacting. The first symbol refers to the first organism mentioned.What interactions exist between a bee and a flower? a. +/+ b. +/o c. +/- d. o/o e. -/-

+/+

The symbols +, -, and o are to be used to show the results of interactions between individuals and groups of individuals in the examples that follow. The symbol + denotes a positive interaction, — denotes a negative interaction, and o denotes where individuals are not affected by interacting. The first symbol refers to the first organism mentioned.What interactions exist between cellulose-digesting organisms in the gut of a termite and the termite? a. +/+ b. +/o c. +/- d. o/o e. -/-

+/+

The symbols +, -, and o are to be used to show the results of interactions between individuals and groups of individuals in the examples that follow. The symbol + denotes a positive interaction, — denotes a negative interaction, and o denotes where individuals are not affected by interacting. The first symbol refers to the first organism mentioned.What interactions exist between a tick on a dog and the dog? a. +/+ b. +/o c. +/- d. o/o e. -/-

+/-

The symbols +, -, and o are to be used to show the results of interactions between individuals and groups of individuals in the examples that follow. The symbol + denotes a positive interaction, — denotes a negative interaction, and o denotes where individuals are not affected by interacting. The first symbol refers to the first organism mentioned.What interactions exist between the cattle egret and grazing cattle? a. +/o b. o/- c. o/o d. +/- e. -/-

+/o

The symbols +, -, and o are to be used to show the results of interactions between individuals and groups of individuals in the examples that follow. The symbol + denotes a positive interaction, — denotes a negative interaction, and o denotes where individuals are not affected by interacting. The first symbol refers to the first organism mentioned.What interactions exist between a lion pride and a hyena pack? a. +/+ b. +/o c. +/- d. o/o e. -/-

-/-

Approximately how many kg of carnivore biomass can be supported by a field plot containing 1,000 kg of plant material? a. 1,000 b. 100 c. 10,000 d. 10 e. 1

10

In July 2008, the United States had a population of approximately 302,000,000 people. How many Americans were there in July 2009, if the estimated 2008 growth rate was 0.88%? a. 2,710,800,000 b. 304,700,000 c. 303,000,000 d. 5,500,000 e. 2,700,000

304,700,000

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 2,600 J for cellular respiration. What is the production efficiency of this owl? a. 1% b. 10% c. 40% d. 0.02% e. 4%

4%

A population of ground squirrels has an annual per capita birth rate of 0.06 and an annual per capita death rate of 0.02. Calculate an estimate of the number of individuals added to (or lost from) a population of 1,000 individuals in one year. a. 20 individuals lost b. 120 individuals added c. 20 individuals added d. 400 individuals added e. 40 individuals added

40 individuals added

Density-dependent factors lead to fewer births and increased mortality.Figure 40.1Which climograph shows the climate for location 1? a. A b. C c. E d. H e. G

A

Examine the food web for a particular terrestrial ecosystem in Figure 42.1. Which species is autotrophic? a. A b. B c. C d. D e. E

A

Figure 42.2 Diagram of a food web (arrows represent energy flow and letters represent species)If Figure 42.2 represents a marine food web, the smallest organism might be a. C. b. I. c. E. d. A. e. F.

A.

Figure 40.2 shows a generalized cross section of the marine environment with various zones labeled with letters. Choose the letter that best answers the question.Figure 40.2Which zone produces the most global oxygen? a. A b. B c. C d. D e. E

B

Use the diagram of a hypothetical food web in Figure 41.3 to answer the following questions. The arrows represent the transfer of energy between the various trophic levels.Figure 41.3Which letter represents an organism that could be a primary producer? a. A b. B c. C d. D e. E

B

Use the diagram of a hypothetical food web in Figure 41.3 to answer the following questions. The arrows represent the transfer of energy between the various trophic levels.Figure 41.3Which letter represents an organism that could be a producer? a. A b. B .c. C d. D e. E

B

Figure 40.2 shows a generalized cross section of the marine environment with various zones labeled with letters. Choose the letter that best answers the question.Figure 40.2Which zone has a condition of constant temperature? a. A b. B c. C d. D e. E

C

The eight climographs in Figure 40.1 show yearly temperature (line graph and left vertical axis) and precipitation (bar graph and right vertical axis) averages for each month for some locations on Earth. Choose the climograph that best answers the question.Which climograph shows the climate for location 5? a. A b. C c. E d. H e. D

C

Figure 42.1 Food web for a particular terrestrial ecosystem (arrows represent energy flow and letters represent species)Examine the food web for a particular terrestrial ecosystem in Figure 42.1. Which pair of species could be omnivores? a. C and D b. A and B c. C and E d. B and C e. A and D

C and E

Figure 40.2 shows a generalized cross section of the marine environment with various zones labeled with letters. Choose the letter that best answers the question.Figure 40.2Which zone has the lowest biomass per unit of area? a. A b. B c. C d. D e. E

D

The eight climographs in Figure 40.1 show yearly temperature (line graph and left vertical axis) and precipitation (bar graph and right vertical axis) averages for each month for some locations on Earth. Choose the climograph that best answers the question.Which climograph shows the climate for location 3? a. D b. E c. B d. F e. C

D

Why do populations grow more slowly as they approach their carrying capacity? a. The incoming energy decreases in populations experiencing a high rate of increase. b. Hormonal changes promote higher death rates in crowded populations. c. Density-dependent factors lead to fewer births and increased mortality. d. Density-independent factors lead to fewer births and increased mortality. e. Individuals voluntarily stop mating so that overcrowding does not occur.

Density-dependent factors lead to fewer births and increased mortality.

Examine the food web for a particular terrestrial ecosystem in Figure 42.1. Which species is most likely a decomposer in this food web? a. A b. B c. C d. D e. E

E

The eight climographs in Figure 40.1 show yearly temperature (line graph and left vertical axis) and precipitation (bar graph and right vertical axis) averages for each month for some locations on Earth. Choose the climograph that best answers the question.Which climograph shows the climate for location 4? a. A b. B c. C d. G e. E

E

Which statement describes how climate might change if Earth was 75% land and 25% water? a. Summers would be longer and winters shorter at midlatitude locations. b. More terrestrial microclimates would be created because of daily fluctuations in climate. c. Terrestrial ecosystems would likely experience more precipitation. d. Earth's daytime temperatures would be higher and nighttime temperatures lower. e. Earth would experience an unprecedented global warming.

Earth's daytime temperatures would be higher and nighttime temperatures lower.

Elephants are not the most dominant species in African grasslands, yet they influence community structure. The grasslands contain scattered woody plants, but they are kept in check by the uprooting activities of the elephants. Take away the elephants, and the grasslands convert to forests or to shrublands. The newly growing forests support fewer species than the previous grasslands. Which of the following describes why elephants are the keystone species in this scenario? a. Elephants are the biggest herbivore in this community. b. Elephants prevent drought in African grasslands. c. Elephants exhibit a disproportionate influence on the structure of the community relative to their abundance. d. Grazing animals depend upon the elephants to convert forests to grassland. e. Elephants help other populations survive by keeping out many of the large African predators.

Elephants exhibit a disproportionate influence on the structure of the community relative to their abundance.

Which statement most accurately describes how matter and energy are used in ecosystems? a. Matter can be converted into energy; energy cannot be converted into matter. b. Matter is used in ecosystems; energy is not. c. Energy flows through ecosystems; matter cycles within and through ecosystems. d. Energy can be converted into matter; matter cannot be converted into energy. e. Matter flows through ecosystems; energy cycles within ecosystems.

Energy flows through ecosystems; matter cycles within and through ecosystems.

The eight climographs in Figure 40.1 show yearly temperature (line graph and left vertical axis) and precipitation (bar graph and right vertical axis) averages for each month for some locations on Earth. Choose the climograph that best answers the question. Which climograph shows the climate for location 2? a. H b. F c. C d. B e. D

F

Why is a pathogen generally more virulent in a new habitat? a. Intermediate host species are more motile and transport pathogens to new areas. b. Hosts in new environments have not had a chance to become resistant to the pathogen through natural selection. c. New environments are almost always smaller in area, so that transmission of pathogens is easily accomplished between hosts. d. More pathogens tend to immigrate into newer habitats. e. Pathogens evolve more efficient forms of reproduction in new environments.

Hosts in new environments have not had a chance to become resistant to the pathogen through natural selection.

A population is correctly defined as having which of the following characteristics? I. inhabiting the same general area II. belonging to the same species III. possessing a constant and uniform density and dispersion a. II and III only b. I only c. I, II, and III d. III only e. I and II only

I and II only

Often the growth cycle of one population has an effect on the cycle of another. As moose populations increase, for example, wolf populations also increase. Thus, if we are considering the logistic equation for the wolf population,dN/dt = rN ,which of the factors accounts for the effect of the moose population? a. K b. dt c. N d. rN e. r

K

Why are food chains relatively short? a. Top-level feeders tend to be more numerous than lower-trophic-level species. b. There are only so many organisms that are adapted to feed on other types of organisms. c. Food chain length is ultimately determined by the photosynthetic efficiency of producers. d. Top-level feeders tend to be small but are capable of conserving more energy. e. Longer chains are less stable and energy transfer between trophic levels is inefficient.

Longer chains are less stable and energy transfer between trophic levels is inefficient.

In ecosystems, why is the term cycling used to describe material transfer, whereas the term flow is used for energy exchange? a. Materials are cycled into ecosystems from other ecosystems, but energy constantly flows within the ecosystem. b. None of the choices is correct. c. Both material and energy are recycled and are then transferred to other ecosystems as in a flow. d. Materials are repeatedly used, but energy flows through and out of ecosystems. e. Both material and energy flow in a never-ending stream within an ecosystem.

Materials are repeatedly used, but energy flows through and out of ecosystems.

Why is net primary production (NPP) a more useful measurement to an ecosystem ecologist than gross primary production (GPP)? a. NPP can be expressed in terms of carbon fixed by photosynthesis for an entire ecosystem. b. NPP represents the stored chemical energy that will be available to consumers in the ecosystem. c. NPP shows the rate at which the standing crop is utilized by consumers. d. NPP is the same as the standing crop. e. NPP can be expressed in energy/unit of area/unit of time.

NPP represents the stored chemical energy that will be available to consumers in the ecosystem.

Which of the following is a correct statement about the McArthur/Wilson Island Equilibrium Model? a. As the number of species on an island increases, the emigration rate decreases. b. Islands closer to the mainland have higher extinction rates. c. Competitive exclusion is less likely on an island that has large numbers of species. d. The more species that inhabit an island, the lower the extinction rate. e. Small islands receive few new immigrant species.

Small islands receive few new immigrant species.

Why do tropical communities tend to have greater species diversity than temperate or polar communities? a. They are less likely to be affected by human disturbance. b. Tropical communities are generally older than temperate and polar communities. c. Tropical communities are low in altitude, whereas temperate and polar communities are high in altitude. d. More competitive dominant species have evolved in temperate and polar communities. e. There are fewer parasites to negatively affect the health of tropical communities.

Tropical communities are generally older than temperate and polar communities.

Which of the following is an example of cryptic coloration? a. colors of an insect-pollinated flower's petals b. a "walking stick" insect that resembles a twig c. brown or gray color of tree bark d. markings of a viceroy butterfly's wings e. bands on a coral snake

a "walking stick" insect that resembles a twig

Which of the following is an example of Batesian mimicry? a. a butterfly that resembles a leaf b. an insect that resembles a twig c. a snapping turtle that uses its tongue to mimic a worm, thus attracting fish d. a nonvenomous snake that looks like a venomous snake e. a fawn with fur coloring that camouflages it in the forest environment

a nonvenomous snake that looks like a venomous snake

Which marine zone has the lowest rates of primary productivity (photosynthesis)? a. intertidal b. pelagic c. continental shelf d. abyssal e. neritic

abyssal

The three basic variables that make up the life history of an organism are a. age when reproduction begins, how often reproduction occurs, and how many offspring are produced per reproductive episode. b. life expectancy, birth rate, and death rate. c. number of reproductive females in the population, age structure of the population, and life expectancy. d. how often reproduction occurs, life expectancy of females in the population, and number of offspring per reproductive episode. e. the number of reproductive females in the population, how often reproduction occurs, and death rate.

age when reproduction begins, how often reproduction occurs, and how many offspring are produced per reproductive episode.

Which of the following locations is the reservoir for carbon in the carbon cycle? a. atmosphere b. fossilized plant and animal remains (coal, oil, and natural gas) c. plant and animal biomass d. sediments and sedimentary rocks e. all of the above

all of the above

Which of the following is an example of an ecosystem? a. all of the organisms and their physical environment in a tropical rain forest b. a pond and all of the plant and animal species that live in it c. all of the brook trout in a 500-square-hectare river drainage system d. the intricate interactions of the various plant and animal species on a savanna during a drought e. the plants, animals, and decomposers that inhabit an alpine meadow

all of the organisms and their physical environment in a tropical rain forest

In which of the following situations would you expect to find the largest number of K-selected individuals? a. a shifting sand dune community of south Lake Michigan b. a newly emergent volcanic island c. an old-growth forest d. a recently abandoned agricultural field in Ohio e. South Florida after a hurricane

an old-growth forest

How did Eugene Odum describe an ecological niche? a. the interactions of the organism with other members of the community b. an organism's "profession" in the community c. the "address" of an organism d. the organism's role in recycling nutrients in its habitat e. an entity that is synonymous with an organism's specific trophic level

an organism's "profession" in the community

Species richness increases a. as community size decreases. b. as we increase in altitude in equatorial mountains. c. as we travel southward from the North Pole to the equator. d. on islands as distance from the mainland increases. e. as depth increases in aquatic communities.

as we travel southward from the North Pole to the equator.

Which of the following locations is the main reservoir for nitrogen in Earth's nitrogen cycle? a. sedimentary bedrock b. plant and animal biomass c. soil d. fossilized plant and animal remains (coal, oil, and natural gas) e. atmosphere

atmosphere

An ecologist recorded 12 white-tailed deer, Odocoileus virginianus, per square mile in one woodlot and 20 per square mile in another woodlot. What was the ecologist comparing? a. cohorts b. range c. density d. dispersion e. carrying capacity

density

Which of the following causes populations to shift most quickly from an exponential to a logistic population growth? a. favorable climatic conditions b. removal of predators c. competition for resources d. increased birth rate e. decreased death rate

competition for resources

Which of the following examples would most accurately measure the density of the population being studied? a. counting the number of coyote droppings per hectare b. counting the number of prairie dog burrows per hectare c. counting the number of zebras from airplane census observations. d. counting the number of times a 1-kilometer transect is intersected by tracks of red squirrels after a snowfall e. counting the number of moss plants in 1-m2 quadrats

counting the number of moss plants in 1-m2 quadrats

In the nitrogen cycle, the bacteria that replenish the atmosphere with N2 are a. methanogenic protozoans. b. denitrifying bacteria. c. nitrifying bacteria. d. nitrogen-fixing bacteria. e. Rhizobium bacteria.

denitrifying bacteria.

Which of the following sets of measurements would best describe a population's physical structure and vital statistics? a. gene frequency over time and the ratio of reproductive to nonreproductive individuals b. annual precipitation averages and mean annual temperatures c. density, dispersion, and demographics d. minimum and maximum amounts of precipitation and annual temperature extremes e. ratio of predators and the number of immigrants and emigrants

density, dispersion, and demographics

Which of the following could be a density-independent factor limiting human population growth? a. social pressure for birth control b. plagues c. earthquakes d. famines e. pollution

earthquakes

Which of the following levels of ecological organization is arranged in the correct sequence from most to least inclusive? a. ecosystem, community, population, individual b. population, ecosystem, individual, community c. community, ecosystem, individual, population d. individual, community, population, ecosystem e. individual, population, community, ecosystem

ecosystem, community, population, individual

Which of the following could qualify as a top-down control on a grassland community? a. influence of temperature on competition among plants b. effect of grazing intensity by bison on plant species diversity c. effect of humidity on plant growth rates d. influence of soil nutrients on the abundance of grasses versus wildflowers e. limitation of plant biomass by rainfall amount

effect of grazing intensity by bison on plant species diversity

Which of the following terms encompasses all of the others? a. secondary consumers b. carnivores c. heterotrophs d. herbivores e. primary consumers

heterotrophs

Natural selection involves energetic trade-offs between a. high survival rates of offspring and the cost of parental care. b. the emigration of individuals when they are no longer reproductively capable or committing suicide. c. increasing the number of individuals produced during each reproductive episode with a corresponding decrease in parental care. d. producing large numbers of gametes when employing internal fertilization versus fewer numbers of gametes when employing external fertilization. e. choosing how many offspring to produce over the course of a lifetime and how long to live.

high survival rates of offspring and the cost of parental care.

Which of the following is most likely to contribute to density-dependent regulation of populations? a. intraspecific competition for nutrients b. earthquakes c. floods d. fires e. the removal of toxic waste by decomposers

intraspecific competition for nutrients

Zoonotic disease a. can only be spread from animals to humans through direct contact. b. can only be transferred from animals to humans by means of an intermediate host. c. is too specific to study at the community level, and studies of zoonotic pathogens are relegated to organismal biology. d. is caused by pathogens that are transferred from other animals to humans by direct contact or by means of a vector. e. is caused by suborganismal pathogens such as viruses, viroids, and prions only.

is caused by pathogens that are transferred from other animals to humans by direct contact or by means of a vector.

In a tide pool, 15 species of invertebrates were reduced to 8 after one species was removed. The species removed was likely a(n) a. mutualistic organism. b. herbivore. c. keystone species. d. pathogen. e. resource partitioner.

keystone species.

If Figure 42.2 represents a terrestrial food web, the combined biomass of C + D would probably be a. greater than the biomass of B. b. greater than the biomass of A. c. less than the biomass of A + B. d. less than the biomass of F. e. less than the biomass of H.

less than the biomass of A + B.

Aquatic primary productivity is most limited by which of the following? a. predation by primary consumers b. increased pressure with depth c. pollution d. temperature e. light and nutrient availability

light and nutrient availability

Which of the following lists of organisms is ranked in correct order from lowest to highest percent in production efficiency? a. insects, fish, mammals b. mammals, fish, insects c. insects, mammals, fish d. mammals, insects, fish e. fish, insects, mammals

mammals, fish, insects

Evidence shows that some grasses benefit from being grazed. Which of the following terms would best describe this plant-herbivore interaction? a. parasitism b. predation c. competition d. mutualism e. commensalism

mutualism

According to the competitive exclusion principle, two species cannot continue to occupy the same a. territory. b. habitat. c. range. d. niche. e. biome.

niche.

Nitrogen is available to plants mostly in the form of a. N2 in the atmosphere. b. nitrate and ammonium ions in the soil. c. uric acid from animal excretions. d. nucleic acids from decomposing plants and animals. e. nitrite ions in the soil.

nitrate and ammonium ions in the soil.

The growing season would generally be shortest in which of the following biomes? a. savanna b. northern coniferous forest c. tropical rain forest d. temperate broadleaf forest e. temperate grassland

northern coniferous forest

Which of the following is characteristic of K-selected populations? a. small offspring b. a high intrinsic rate of increase c. offspring with good chances of survival d. many offspring per reproductive episode e. early parental reproduction

offspring with good chances of survival

Which of these ecosystems accounts for the largest amount of Earth's net primary productivity? a. tropical rain forest b. salt marsh c. tundra d. open ocean e. savanna

open ocean

Dwarf mistletoes are flowering plants that grow on certain forest trees. They obtain nutrients and water from the vascular tissues of the trees. The trees derive no known benefits from the dwarf mistletoes. Which of the following best describes the interactions between dwarf mistletoes and trees? a. parasitism b. facilitation c. competition d. commensalism e. mutualism

parasitism

Trees are not usually found in the tundra biome because of a. insufficient annual precipitation. b. extreme winter temperatures. c. acidic soils. d. permafrost. e. overbrowsing by musk ox and caribou.

permafrost.

Which of the following are important biotic factors that can affect the structure and organization of biological communities? a. temperature, water b. predation, competition c. precipitation, wind d. light intensity, seasonality e. nutrient availability, soil pH

predation, competition

A cow's herbivorous diet indicates that it is a(n) a. producer. b. primary consumer. c. secondary consumer. d. autotroph. e. decomposer.

primary consumer.

The major role of detrivores in ecosystems is to a. return energy lost to the ecosystem by other organisms. b. prevent the buildup of the inorganic remains of organisms, feces, and so on. c. provide a nutritional resource for heterotrophs. d. recycle chemical nutrients to a form capable of being used by autotrophs.

recycle chemical nutrients to a form capable of being used by autotrophs.

he major role of detritivores in ecosystems is to a. recycle chemical nutrients to a form capable of being used by autotrophs. b. prevent the buildup of the organic remains of organisms, feces, and so on. c. return energy lost to the ecosystem by other organisms. d. provide a nutritional resource for heterotrophs.

recycle chemical nutrients to a form capable of being used by autotrophs.

Exponential growth of a population is represented by dN/dt = a. rN (K + N). b. rN . c. . d. rN . e. rmax N.

rmax N.

How does phosphorus normally enter ecosystems? a. cellular respiration b. rock weathering c. atmospheric phosphorous gas d. photosynthesis e. vulcanism

rock weathering

Which of the following best describes resource partitioning? a. slight variations in a species' niche that allow similar species to coexist b. differential resource utilization that results in a decrease in community species diversity c. competitive exclusion that results in the success of the superior species d. a climax community that is reached when no new niches are available e. two species that can coevolve to share identical niches

slight variations in a species' niche that allow similar species to coexist

Which trophic level is most vulnerable to extinction? a. decomposer level b. tertiary consumer level c. primary consumer level d. producer level e. secondary consumer level

tertiary consumer level

Which of the following is an example of aposematic coloration? a. eye color in humans b. a katydid whose wings look like a dead leaf c. green color of a plant d. the brightly colored patterns of poison dart frogs e. colors of an insect-pollinated flower

the brightly colored patterns of poison dart frogs

Subtraction of which of the following will convert gross primary productivity into net primary productivity? a. the energy used by heterotrophs in respiration b. the energy contained in the standing crop c. all solar energy d. the energy used by autotrophs in respiration e. the energy fixed by photosynthesis

the energy used by autotrophs in respiration

Carrying capacity is a. determined by density and dispersion data. b. fixed for most species over most of their range most of the time. c. the maximum population size that a particular environment can support. d. the term used to describe the stress a population undergoes due to limited resources. e. seldom reached by marine producers and consumers because of the vast resources of the ocean.

the maximum population size that a particular environment can support.

Trophic efficiency is a. the ratio of net secondary production to assimilation of primary production. b. the percentage of production transferred from one trophic level to the next. c. a measure of how nutrients are cycled from one trophic level to the next. d. usually greater than production efficiencies. e. about 90% in most ecosystems

the percentage of production transferred from one trophic level to the next.

In models of logistic population growth, a. new individuals are added to the population most rapidly at the beginning of the population's growth. b. carrying capacity is never reached. c. new individuals are added to the population as N approaches K. d. only density-dependent factors affect the rate of population growth. e. the population growth rate slows dramatically as N approaches K.

the population growth rate slows dramatically as N approaches K.

The feeding relationships among the species in a community determine the community's a. ecological niche. b. trophic structure. c. species richness. d. species-area curve. e. secondary succession.

trophic structure

Which of these ecosystems has the highest net primary productivity per square meter annually? a. savanna b. boreal forest c. tropical rain forest d. temperate forest e. open ocean

tropical rain forest

Which of the following ecosystems would likely have a larger net primary productivity/hectare, and why? a. cave due to the lack of photosynthetic autotrophs b. tropical rain forest because of the high species diversity c. open ocean because of the total biomass of photosynthetic autotrophs d. tundra because of the incredibly rapid period of growth during the summer season e. a temperate grassland because of the small standing crop biomass that results from consumption by herbivores and rapid decomposition

tropical rain forest because of the high species diversity

Photosynthetic organisms are unique to most ecosystems because they a. convert light energy into matter. b. use light energy to synthesize organic compounds from inorganic compounds. c. use chemical energy to synthesize organic compounds. d. synthesize organic compounds they obtain from decaying heterotrophs. e. synthesize inorganic compounds from organic compounds.

use light energy to synthesize organic compounds from inorganic compounds.

Which of the following organisms is incorrectly paired with its trophic level? a. eagle—tertiary consumer b. zooplankton—primary producer c. cyanobacterium—primary producer d. grasshopper—primary consumer e. fungus—detritivore

zooplankton—primary producer