Mastering Biology Practice Test

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• Which result would best support the claim that kelp distribution is limited by sea urchin abundance?
• What does the red line on the climatograph represent?
• In the first experiment, which variable is manipulated by the researchers?
• Ignoring migration, which shape describes an age structure likely to remain stable in size?
• As population approaches carrying capacity, environmental resistance ______.
• Which inference follows from the finding that kelp cover increases after removing sea urchins?
• Select the correct statement about the global carrying capacity for the human population.
• In the provided population growth data, during which interval did the population increase the most?
• Changes in the eyes of species 1 after species 2 became established illustrate which ecological concept?
• Which population size has the highest growth rate among those above carrying capacity?
• The change in roosting habits of species 1 after species 2 became established is an example of which concept?
• Which barnacle species would occupy the left half of the rock at the end of summer if niche differentiation occurred between Chthamalus and Balanus?
• Cellulose-digesting microorganisms live in the guts of termites and ruminant mammals. This relationship is an example of _____.
• Directional selection is best described as
• In 1985, China’s rate of population increase was nearly 15 per 1,000. Based on prereproductive population, this projection is:
• In the logistic growth model, what happens to the growth rate as population size nears carrying capacity?
• Approximately how many 15-19-year-old males were there in China in 2010?
• Which statement about carrying capacity estimates is true?
• If competing species are removed from an area, a population's realized niche would most closely resemble its
• Which statement best describes what the bars illustrate?
• Oyster populations are primarily composed of which age class?
• What do the vertical blue bars on this graph represent?
• Which factor is not typically considered in basic population dynamics models focused on size changes?
• With rmax = 1.0 and K = 1,500, what is the general effect on the population growth rate when N exceeds the carrying capacity?
• What describes the pattern of precipitation on the climatograph?
• In species with a Type II survivorship curve, individuals are no more likely to die at one life-stage than another.
• From 1500 to 2010, the human population approximately followed the exponential growth model.
• Which statement is true about the relationship between a species' fundamental and realized niches?
• Which statement best explains why carrying capacity estimates vary across studies?
• Among the four reported growth rates for Ns greater than carrying capacity, which value is the highest (least negative)?
• If a population's environment favors darker fur on dark rocks, which type of selection is acting?
• The rate of human population growth is increasing.
• Momentum explaining the large 1986–1990 birth cohort is attributed to which age-group?
• Which statement describes parasitism?
• What is represented by the distance between two vertical white gridlines on this graph?
• Which statement best describes density-dependent population regulation?
• If two populations have the same birth and death rates but different generation times, which has the higher intrinsic rate of increase?
• Between which years did the world population double according to the graph?
• Which of the following best describes the purpose of a scatter plot in ecological data?
• What is the best estimate of the total yearly precipitation in the region?
• Which equation represents the logistic growth rate of a population?
• What does a negative growth rate indicate about population dynamics?
• The term used to describe a harmless organism resembling a harmful one is _____.
• Which scenario is an example of density-independent population regulation?
• Why is a scatter plot an appropriate type of graph for presenting the data from the second experiment?
• Which statement reflects the competitive exclusion principle?
• Which observation would best support the occurrence of character displacement for body size in a salamander species pair in sympatry?
• Based on the dataset, at which interval does the population begin to show diminishing gains, approaching the carrying capacity?
• If birth rate remains constant but death rate increases, what happens to population growth rate?
• What is a lemur?
• In logistic growth, when N exceeds K, what is the typical sign of the growth rate?
• The full range of resources a species could use in the absence of competition is called its fundamental niche.
• If rmax is doubled, how would the four population growth rates change?
• When species 2 is present, roosting areas one to two stories tall form the realized niche of species 1. Which term describes this narrower niche?
• In a predation interaction, which statement best describes the effect on the predator and prey?
• What unit is used with the red line on climatographs?
• Which condition favors big-bang reproduction?
• The statement that the world population increased from less than 2 billion to more than 6 billion during the 20th century is:
• Which biome does this climatograph represent?
• Which statement best describes the relationship between density-dependent factors and negative feedback?
• A population with a broad-based pyramid-shaped age structure is characteristic of which growth pattern?
• A population is most likely to experience exponential growth when resources are abundant and the initial population size is small.
• Which statement defines carrying capacity?
• Which term applies to the relationship between a dog and a blood-sucking tick?
• Which action would have no effect on carrying capacity K?
• Why is a percentage scale used on the x-axis rather than actual ages?
• What percent of the plant species found on Madagascar are unique to that island?
• According to MacArthur and Wilson's island biogeography theory, immigration and extinction rates on a given island mainly depend on which factors?
• Which statement best describes what the bars illustrate?
• Resource partitioning among coexisting species typically leads to which outcome?
• The human population of Madagascar doubles about every how many years?
• If the researchers repeated this experiment, predict how the results would change for areas where cane toads have been present for 40-60 years.
• Which factor does not contribute to environmental resistance?
• Stabilizing selection tends to
• Humans who have pets tend to be healthier than humans who do not have pets. Which term describes the relationship between a human and a pet?
• What is the best biological explanation for why the population growth rate became negative between days 70 and 105?
• Which description best defines the fundamental niche?
• A human eats a deer. Which ecological term describes the relationship?
• If the distance between gridlines represents 50 years, how many such intervals are needed to span 100 years?
• Carrying capacity is best described as:
• What does overshooting the carrying capacity mean in population dynamics?
• The reintroduction of wolves to Yellowstone is expected to cause what effect on elk populations?
• Stabilizing selection is best described as
• Which day range indicates a negative growth rate for the Daphnia population?
• Ignoring migration, which shape describes an age structure likely to decrease in size?
• Which statement correctly describes the fundamental niche and the realized niche?
• Which curve best describes survivorship in marine molluscs?
• Type II survivorship implies which pattern of death risk across ages?
• The term 'niche' refers to
• For rmax = 2.0, which sequence correctly lists the growth rates for the four Ns above carrying capacity?
• Based on the scatter plot, what conclusion would you draw about whether exposure to cane toads is having a selective effect on black snakes?
• In Connell's classical competitive exclusion experiment with barnacles, which action was the third step?
• Which statement accurately describes the relationship between a species' realized and fundamental niches?
• Which of these is a starting point for primary succession?
• Which group typically exhibits a mortality rate that remains fairly constant across an individual's life span?
• The competition between the two bat species for roosting areas is an example of which type of interaction?
• What is the best biological explanation for why the population stayed below the carrying capacity between days 100 and 160?
• Big-bang reproduction is favored under which condition?
• Parasitism is which type of interspecific interaction?
• Much of the original forest cover on Madagascar has been destroyed primarily as a result of which activity?
• Which predator avoidance method would best describe an octopus blending with its surroundings?
• Which of the following best describes the yearly temperature range shown?
• In an ecosystem, phytoplankton are which trophic level?
• An egret eats insects stirred up by grazing animals. Which term describes the relationship between the egret and the grazing animal?
• Which term best describes exponential population growth that forms a J-shaped curve?
• Which of the following statements best describes logistic growth?
• Which of the following best describes a habitat mosaic?
• Which description matches logistic (density-dependent) population growth?
• Which factor does not affect a habitat's carrying capacity?
• Which processes increase a population's size?
• If the population density is 10 MendAliens per hectare, how many MendAliens would occupy one square kilometer?
• Which statement about density-independent growth is true?
• White-band disease in Caribbean coral reef communities is best described as which type of ecological effect?
• In a community with competition for overlapping resources, what ecological process reduces overlap by dividing resources among species?
• Resource partitioning among coexisting species typically leads to which statement?
• Which action would most directly decrease carrying capacity K for the population?
• Which statement best describes character displacement in ecology?
• Which of the following is considered a density-independent factor in population growth?
• True or false: The per capita rate of increase depends on the age of breeding and the number of offspring produced each year.
• Ignoring migration, which shape describes an age structure likely to increase in size?
• The statement 'China experienced a baby boom after World War II' is:
• In a population dynamics graph with two axes, what does the right y-axis typically represent?
• Which organism has a survivorship curve similar to that of humans?
• Currently, how large is the worldwide population of humans relative to Earth's carrying capacity for humans?
• Which of the following best illustrates ecological succession?
• Which two months have the highest average temperature?
• Which predator avoidance strategy is illustrated by mimicry between hornet moth and paper wasp, and by viceroy and monarch butterflies?
• What do the blue bars on the climatograph represent?
• Which statement best defines the realized niche?
• A broad-based pyramid-shaped age structure indicates which growth pattern?
• Which action would increase carrying capacity K for a local mouse population?
• Which statement about age pyramids is true?
• What is the predicted carrying capacity of the Daphnia culture?
• In populations where two species compete, natural selection due to interspecific competition is most evident in which context?
• If the MendAliens density is 10 per hectare, how many MendAliens would live on 5 hectares?
• Which ecological process describes the exclusion of a species from a resource due to competition?
• Commensalism is which type of interspecific interaction?
• Which statement about exponential growth in population is true?
• What is the general pattern of survivorship for Type I curves?
• Did the Daphnia population ever experience a negative growth rate?
• Which statement is true about a population at carrying capacity?
• Which statement correctly describes energy transfer in a predation interaction?
• Keystone species are those species _____.
• At 50% of maximum life span, survivorship for a Type I curve is:
• An organism's 'trophic level' refers to _____.
• If an organism is a primary consumer, what does it feed on?
• Which example illustrates a mutualistic relationship?
• According to this graph, species with a Type III curve typically produce large numbers of offspring.
• Resource competition, territoriality, disease, and toxic wastes contribute to what kind of regulatory feedback in populations?
• The mark-recapture method would be best for sampling a population of _____.
• Why is the x-axis scaled as a percentage of maximum life span?
• What is the cause of the red color of the waters around Madagascar?
• The unusually large cohort of children born in 1986–1990 is best explained by which phenomenon?
• According to the principle of competitive exclusion, two species cannot continue to occupy the same ecological niche.
• Which biome best matches a climate showing cool to cold winters and warm summers in a temperate zone?
• What are population dynamics?
• In logistic growth, if the population size N exceeds the carrying capacity K, what happens?
• What was the first major event that stimulated an increase in the human population?
• Which organisms tend to have a survivorship curve similar to that described for oysters?
• Humans and sharks both eat fish. What term describes their relationship?
• Disturbances creating patches of different habitat types across a landscape are described by which concept?
• Which statement about Type II survivorship curves is correct?
• Does the measured growth match the predicted growth pattern?
• Which of the following animals has a survivorship curve most similar to that of humans?
• In a mark-recapture study, initially catching and marking 130 MendAliens, releasing them, then capturing 90 with 20 marked, what is the estimated population size?
• Carrying capacity can change with resource availability and environmental conditions. Is this statement true?
• In F. E. Clements' view of community organization, which statement best describes how species function within a community?
• What is a commonly cited effect of moderate disturbances on local biodiversity?
• What is the independent variable in the study examining cane toads' effect on black snakes?
• Which statement about the 20th-century population trend is correct?
• What result offers the best support for the hypothesis that sea urchin abundance limits kelp distribution?
• Two bat species compete for the same roosting areas. This is an example of which type of interspecific interaction?
• Which pattern describes a landscape with discrete patches of habitat of different types created by disturbances?
• On an island with 200 MendAliens living on 20 hectares, what is the population density in MendAliens per hectare?
• What is represented on the x-axis of the survivorship graph?
• Environmental heterogeneity in a landscape most directly contributes to
• What was the third major event that stimulated an increase in the human population?
• Why is a bar graph an appropriate type of graph for presenting the data from the first experiment?
• Which pattern does the line in a population growth graph that levels off represent?
• Which statement describes how species can coexist by using resources in different ways?
• Which factor is most likely to limit population growth as carrying capacity is approached?
• What was the second major event that stimulated an increase in the human population?
• What is carrying capacity?
• In logistic growth, which description best characterizes the pattern?
• A moderate disturbance such as a severe thunderstorm is most likely to result in which landscape pattern?
• If two distinct habitats favor extreme phenotypes, the resulting selection is
• Disruptive selection is characterized by
• Under which of the following conditions would a population most likely experience exponential growth?
• For a species with a Type II survivorship curve, less than ____% of individuals survive for 50% of the maximum life span.
• From 1500 to 2010, the population growth is described as which model?
• The most likely reason that the growth rate leveled off is that the environment reached carrying capacity.
• What does the scatter plot suggest about selection pressure from cane toad exposure?
• If the island covered 40 hectares while the MendAliens number remained the same, what would be the population density?
• If a population is not migrating and births equal deaths, which shape best describes its age structure?
• In a country, in 1970 average age of childbearing was 28 and average offspring per woman was 3. In 1980, average age of childbearing remained 28 but average offspring per woman dropped to 2, with death rate constant. How did the population growth rate change from 1970 to 1980?
• What primarily limits the length of a food chain?
• If rmax is doubled from 1.0 to 2.0, what is observed about the four growth rates for Ns > K?
• Jimsonweed toxins and skunk spray illustrate which predator avoidance strategy?
• For a Type III curve, most individuals reach the maximum life span.
• The total population size is projected to increase through the middle of the 21st century.
• Approximately how many 15-19-year-old males were there in China in 2010?
• Which statement describes logistic growth as population approaches carrying capacity?
• The curve label for molluscs survivership is which of the following?
• Sea urchin spines, snail shells, and rosebush thorns illustrate which predator avoidance strategy?
• Two countries have identical fertility rates (three children per woman) but different average ages of childbearing: country A is 26 years and country B is 30 years. Which statement must be true about comparing their population growth rates?
• What trend is observed in the species–area relationship for islands?
• Which statement describes density-independent population regulation?
• Which statement best describes how ecological succession proceeds in a new environment?
• When is a bar graph preferable to show differences between two groups?
• Which statement best describes exponential growth starting from a small population with abundant resources?