Chapter 16: Biology

According to the population growth equation, logistic growth slows when: K decreases until it is equal to the growth rate. (K—N) becomes infinitely large. r x N is larger than K. a calamity, such as an earthquake, occurs. (K—N) approaches zero.

(K—N) approaches zero.

Which factor suggests that humans have reached our carrying capacity? Humans are unable to increase food production to sustain a larger population. Humans have exhausted available space. Human predators are drastically reducing population size. Humans' use of resources in general is greater than resource availability. There is no evidence that humans have reached carrying capacity.

Humans' use of resources in general is greater than resource availability.

An external force on a population that increases the risk of death is known as: a density-independent factor. a survivorship curve. aging. a hazard factor. mortality.

a hazard factor.

Which mammal would you expect to have the shortest gestation period? a mouse a chimpanzee an elephant a giraffe a human

a mouse

Life history patterns: have no genetic component. exist only in organisms that exhibit parental care. are subject to the pressures of natural selection. show up in the fossils of plants. are usually learned.

are subject to the pressures of natural selection.

If a population starts with 500 individuals, and during the year 50 of those individuals die, then the annual death rate is: 10. The annual death rate cannot be computed from the information provided. 1/50. 0.1. 0.01.

0.1.

In a population exhibiting logistic growth, the rate of population increase is greatest when N is: 0.5K. K. 0.75K. very low. 5K.

0.5K.

In a population exhibiting logistic growth, the rate of population increase is greatest when N is: very low. 5K. K. 0.5K. 0.75K.

0.5K.

The 20 adult females in a small population each have a probability of 0.5 of producing a single offspring each year and a probability of 0.5 of producing no offspring. How many female offspring will be produced each year? 20 offspring per year on average, with some variation around this average 50 offspring, because a female can produce twin and triplet births exactly 20 offspring per year exactly 10 offspring per year 10 offspring per year on average, with some variation around this average

10 offspring per year on average, with some variation around this average

If r = 1.05 for a population at a given time (t) when N = 100, what will the population size be at time t + 2 (two generations later)? 1.05 110 100 111 105

110

Approximately what was the human population of the world in the year 1950? 2.5 billion 1.6 billion 850 million 650 million 4.8 billion

2.5 billion

Approximately what was the human population of the world in the year 1950? 850 million 1.6 billion 2.5 billion 650 million 4.8 billion

2.5 billion

A population of scarab beetles has an annual per capita birth rate of 0.8 and an annual per capita death rate of 0.5. Estimate the number of individuals added to or lost from a population of 1,000 individuals in one year. 3,000 individuals added 50 individuals lost 500 individuals lost 300 individuals added 30 individuals added

300 individuals added

Because current birth rates are outpacing death rates, earth's human population is increasing by about _____ each year. 80 million people 1 billion people 50 million people 100 million people 40 million people

80 million people

Which is characteristic of big-bang reproduction? There is only one reproductive event. There is a single intensive mating period. Parents often die shortly after the mating/reproduction period. A large number of offspring are produced. After an intensive mating period, a large number of offspring are produced in a single reproductive event. The parents often die following the mating/reproduction period

After an intensive mating period, a large number of offspring are produced in a single reproductive event. The parents often die following the mating/reproduction period

What is a significant distinction between annuals and perennials? Annuals have low investment in their offspring, whereas perennials have high investment. Annuals reproduce once before dying, whereas perennials reproduce repeatedly. Annuals have high investment in their offspring, whereas perennials have low investment. Annuals reproduce repeatedly, whereas perennials reproduce once before dying. Annuals produce fewer offspring over the lifetime compared to perennials.

Annuals reproduce once before dying, whereas perennials reproduce repeatedly.

When a population reaches carrying capacity (K), it appears to persist indefinitely. One assumption could be that organisms stop dying. Which statement is a more likely explanation for this observation? More organisms are arriving into the population than leaving. The population is growing so quickly that it overshoots its carrying capacity. The number of individuals arriving is exactly the same as the number of individuals leaving. As a population gets closer to the carrying capacity of its environment, its growth stops. The rate of population growth is dependent on the resources available.

As a population gets closer to the carrying capacity of its environment, its growth stops.

Which statement best exemplifies the difference between a population and an individual? Evolution does not occur within the individual and population ecology examines features not present in the individual, such as birth, death, and immigration rates, that can be measured in populations. Population ecology examines features that cannot be studied on an individual organism. Behavior is not studies at the individual level, but is studies at the population level. Birth rates, death rates, immigration rates, and so on are features possessed by populations, not individuals. Evolution does not occur within the individual.

Evolution does not occur within the individual and population ecology examines features not present in the individual, such as birth, death, and immigration rates, that can be measured in populations.

Exponential growth can continue indefinitely only if: the population starts out very small. Exponential growth cannot continue indefinitely. the carrying capacity of the habitat (K) is a moderate figure. the carrying capacity of the habitat (K) is very high. the population starts out high but grows slowly.

Exponential growth cannot continue indefinitely.

On average, which leaves more offspring that survive to become adults and reproduce: a pair of elephants or a pair of rabbits? The pair of elephants will leave more because any individual elephant born is more likely to survive to become an adult and reproduce. The pair of elephants will leave more because elephants live much longer and have more breeding seasons. If both populations are stable, then the pair of elephants and the pair of rabbits will leave the same number of offspring that survive to become adults and reproduce. The pair of rabbits will leave more because they have so many more offspring per breeding season than a pair of elephants. The pair of rabbits will leave more because they reach sexual maturity more rapidly.

If both populations are stable, then the pair of elephants and the pair of rabbits will leave the same number of offspring that survive to become adults and reproduce.

In the age pyramids depicted here, the country on the left could be _________________, whereas the country on the right could be _________________. Kenya; Tanzania Thailand; Canada Kenya; Norway Canada; Kenya Norway; Sweden

Kenya; Norway

Which statement about natural selection is true? Natural selection "weeds out" alleles that cause death in early life. Natural selection tends to increase the risk of dying from external forces. Natural selection operates only on people of advanced age. Natural selection has produced a high degree of infant mortality in humans, compared to other species. Natural selection has produced increasing numbers of people who choose never to have children.

Natural selection "weeds out" alleles that cause death in early life.

Which describes the life history of a species with a fast, intensive reproductive investment? Humans produce few offspring throughout multiple reproductive episodes. Mature bamboo produces thousands of seeds and then dies. Mayflies emerge in their adult form, only to reproduce and die one hour later. Pandas produce only one or two offspring per year, but can reproduce for multiple years. Sea urchins spawn multiple times each season and produce millions of offspring each time they spawn.

Sea urchins spawn multiple times each season and produce millions of offspring each time they spawn.

What prediction can be made about the birth and death rates of the population at point 5 on the graph? The birth rate is slightly lower than the death rate. The birth rate is much higher than the death rate. The birth rate is slightly higher than the death rate. The birth rate is much lower than the death rate. The birth rate is approximately equal to the death rate.

The birth rate is approximately equal to the death rate.

How does exponential growth differ from logistic growth? Exponential growth models include consideration of a population's carrying capacity. Logistic growth requires a large population. Logistic growth models take the population's age structure into account. Long-term exponential growth is more commonly observed than long-term logistic growth in nature. The logistic model of growth incorporates environmental limitations on population size.

The logistic model of growth incorporates environmental limitations on population size.

What is the difference between maximum yield and maximum sustainable yield? The maximum yield would be harvesting the entire population, whereas the maximum sustainable yield is harvesting 10% or less of the carrying capacity. The maximum sustainable yield would be harvesting the entire population, whereas the maximum yield is harvesting 90% of the carrying capacity. The maximum yield would be harvesting the entire population, whereas the maximum sustainable yield is harvesting 90% of the carrying capacity. The maximum yield would be harvesting the entire population, whereas the maximum sustainable yield is harvesting half of the carrying capacity. The maximum sustainable yield would be harvesting the entire population, whereas the maximum yield is harvesting half of the carrying capacity.

The maximum yield would be harvesting the entire population, whereas the maximum sustainable yield is harvesting half of the carrying capacity.

Which characteristic is associated with a species whose life history strategy has a greater longevity and survival rate? They have large numbers of offspring whenever they reproduce. They have many natural predators. They produce large numbers of gametes during reproduction. They do not provide much parental care to their offspring. Their rate of population growth is low.

Their rate of population growth is low.

Which statement best describes expectations for the world's human population by the year 2021? Negative growth in the United States and Europe will counterbalance positive growth in the developing countries. It will drop below 6 billion if the current rate of decrease continues. The problem is too complex to make any predictions. There will be slightly less than 8 billion people if the current rate of growth continues. It will exceed 10 billion if the current rate of increase continues.

There will be slightly less than 8 billion people if the current rate of growth continues.

Field mice have few natural defenses. What other characteristics are also likely to be true about field mice? They age slowly. They have a low risk of death at each age. They have long life spans. They reach sexual maturity early. They live with low risk of predation.

They reach sexual maturity early.

Which statement is true of giant tortoises? They evolved in environments with high mortality risk. They evolved in environments with a high hazard factor. They have a high risk of death at any age. They tend to reproduce early and often. They tend to age later and have long life spans.

They tend to age later and have long life spans.

Which statement is true of giant tortoises? They tend to age later and have long life spans. They evolved in environments with high mortality risk. They have a high risk of death at any age. They tend to reproduce early and often. They evolved in environments with a high hazard factor.

They tend to age later and have long life spans.

What is likely to be true about a species that lives with a high hazard factor, such as rodents? They would have few offspring per reproductive event. They would have long life spans. They would exhibit early aging. They would have unlimited resources available to them. They would have an accumulation of harmful mutations, which have their effects late in life.

They would exhibit early aging.

What is the best description of "demographic transition"? a pattern of growth, experienced as a country industrializes, characterized by slow growth, then fast growth, then slow growth again the change among different races of people across different geographic regions a pattern of population growth that is experienced as a country industrializes The change among different races of people across different geographic regions as those regions industrialize a pattern of growth characterized by slow growth, then fast growth, then slow growth again

a pattern of growth, experienced as a country industrializes, characterized by slow growth, then fast growth, then slow growth again

The age-structure diagram of a human population in a developing country has the shape of: an hourglass. a totem pole. a pyramid. a funnel. a rectangle.

a pyramid.

Which defines the reproductive investment of a species? the likelihood of death from a reproductive event all of the material and energetic contribution that an individual will make to its offspring the maximum number of offspring supported by an environment the ability to continually double the size of a population over time the number of individuals within a population of reproductive age

all of the material and energetic contribution that an individual will make to its offspring

What life history trade-off characterizes big-bang reproducers, such as salmon? an exceptionally high reproductive investment and early death production of a few large eggs and better survival of offspring delayed reproduction and great longevity high parental investment and a large number of offspring delayed reproduction and significant growth

an exceptionally high reproductive investment and early death

Aging is: an increased risk of dying with increasing age. an increased risk of free-radical production that results in the loss of skin elasticity. the underlying cause of all deaths, despite the initial appearance of accidents. a reference to the change in aesthetics over time in an individual. the technical term for DNA loss over years.

an increased risk of dying with increasing age.

Most ecological processes cannot be observed or studied within: a population. microbial species. an individual. an ecosystem. a community.

an individual.

Natural populations fluctuate through time. One of the forces causing variation in population size is variation in the physical environment, which can have both direct and indirect effects on populations. Variation in population size linked to environmental factors (aside from those that occur daily or seasonally) is likely to: be irregular, perhaps even random. be predictable and constant. affect the biotic potential exponentially. be density-dependent. track the logistic growth model.

be irregular, perhaps even random.

The per capita growth rate, r, of a population is a calculation of which two factors? birth rate minus death rate death rate multiplied by 0.5 birth rate multiplied by 0.5 death rate multiplied by the population now (N) birth rate multiplied by the population now (N)

birth rate minus death rate

Natural selection: does not influence aging because aging is determined by an individual's environment. cannot reduce the frequency of alleles that cause mortality among individuals who have not yet reached the age of maturity. cannot weed out from a population any alleles that do not reduce an individual's relative reproductive success, even if these alleles increase an individual's risk of dying. can influence aging but not longevity. leads to an increase in the frequency of any illness-inducing alleles that have their effect when an organism can reproduce.

cannot weed out from a population any alleles that do not reduce an individual's relative reproductive success, even if these alleles increase an individual's risk of dying.

The number of individuals that can be supported in a given habitat is the: innate capacity for increase. biotic potential. density-dependent effect. density-independent effect. carrying capacity.

carrying capacity.

The population size that a particular habitat can support indefinitely is called the: intrinsic population size. carrying capacity. fundamental niche. survivorship curve. realized niche.

carrying capacity.

The population size that a particular habitat can support indefinitely is called the: realized niche. carrying capacity. intrinsic population size. fundamental niche. survivorship curve.

carrying capacity.

A survivorship curve that had low survivorship in the beginning and stabilized after high initial mortality would be a characteristic of which type of organism? cod hummingbirds rodents birds of prey elephants

cod

Which term best describes populations of different species that interact with each other within a locale? population maximum sustainable yield community ecosystem ecology

community

What factor does not lead to a reduction in birth and death rates? improved health care higher levels of education higher levels of employment a higher standard of living decreased resource availability

decreased resource availability

Disease is spread more quickly between individuals who live in close proximity, such as in a nesting colony of penguins. Disease can be considered a(n): factor that causes a greater birth rate than death rate. exponential growth factor. density-independent factor. density-dependent factor. factor that increases carrying capacity.

density-dependent factor.

Which factor favors early reproduction? stable environment later aging early risk of death long life spans low risk of predation

early risk of death

The study of the relationships between all living organisms and their environments is known as _____. carrying capacity biology population ecology ecology zoology

ecology

Which term best describes all of the living organisms, as well as non-living elements, that interact in a particular area? ecology population community maximum sustainable yield ecosystem

ecosystem

Which choice best exemplifies an organism with a type 1 survivorship curve? annual plants oysters sea turtles mackerel elephants

elephants

In which region would you expect mammals to have small, frequent litters? arctic tundra of Greenland deciduous forests of North America deserts of North Africa coniferous forests of Eurasia equatorial rainforests of South America

equatorial rainforests of South America

When a population's size is increasing in proportion to its current size,that population is experiencing _____ growth. logarithmic exponential linear negative positive

exponential

In the graph depicted here, curve B is the ____________________, and the orange line (labeled A) represents the ___________________. logistic growth curve; exponential growth curve exponential growth curve; logistic growth curve carrying capacity; logistic growth curve logistic growth curve; carrying capacity exponential growth curve; carrying capacity

exponential growth curve; carrying capacity

In the graph depicted here, curve B is the ____________________ and curve C is the ___________________. logistic growth curve; maximum sustainable yield logistic growth curve; exponential growth curve lazy S curve; sharp S curve logistic growth curve; carrying capacity exponential growth curve; logistic growth curve

exponential growth curve; logistic growth curve

A female rabbit reaches reproductive maturity at about six months of age. Both young and adult rabbits are highly subject to predation. Which reproductive strategy do rabbits likely exhibit? slow, intensive reproductive investment fast, intensive reproductive investment fast, gradual reproductive investment slow, gradual reproductive investment big-bang reproduction

fast, intensive reproductive investment

Which statement about what life histories are based upon is false? the age of reproduction and number of reproductive events the rate of growth and development litter size the age at death food source

food source

Which is NOT an example of a density-independent factor? earthquake lightning strike fungal infection forest fire flood

fungal infection

Which level is NOT studied in ecology? ecosystems populations individuals communities genomes

genomes

Which is a major trade-off in life histories? size for life span growth for reproduction size of offspring for number of reproductive events number of reproductive events for number of offspring per reproductive event size of offspring for amount of parental investment

growth for reproduction

Life extension: is not possible in the wild, but has been achieved in the laboratory. has been achieved in the laboratory by selectively breeding individuals with the earliest age of maturity. can be achieved in species by selectively breeding individuals with the earliest age of maturity. is not possible in the wild because natural selection cannot weed out disease-causing alleles that have an effect only after reproductive age. has been achieved in the laboratory.

has been achieved in the laboratory.

Disease-causing alleles that cause mortality in old age: increase reproductive output. decrease the age of the first reproductive event. decrease the number of offspring produced in a lifetime. have no effect on reproductive output. are dependent on numerous environmental factors.

have no effect on reproductive output.

Type I survivorship curves are seen in both _____ populations. mackerel and tortoise human and tortoise mackerel and kingfisher human and mackerel kingfisher and tortoise

human and tortoise

In order to discern true cause-and-effect relationships it is essential to: Which species does NOT have a type III survivorship curve? randomize subjects to treatment groups. design an experiment to assess the association between two factors. observe relationships between two variables. include as many variables as possible. carefully select subjects for different control groups. most insects mackerel humans oysters most plants

humans

The risk of dying _____ as an individual gets older. decreases, but only if the individual produces offspring is determined only by environmental factors remains the same decreases increases

increases

Which list shows the correct order of ecological levels, from lowest to highest in complexity? individuals > populations > communities> ecosystems populations > communities > individuals > ecosystems ecosystems > communities > individuals > communities individuals > populations > ecosystems > communities communities > populations > ecosystems > individuals

individuals > populations > communities> ecosystems

Which individuals did researchers select to breed in the fruit fly population experiment? individuals that were able to go without food for ten weeks individuals that chose a nutrient source higher in protein individuals that were able to find a mate and reproduce the fastest individuals that produced eggs at ten weeks instead of two weeks individuals that had been genetically altered by the researchers

individuals that produced eggs at ten weeks instead of two weeks

If a country's age pyramid has a narrow base, this indicates that its population: is experiencing a demographic transition. has ample resources to support the older population. is decreasing in size. is made up of mostly young individuals. has little availability to health care.

is decreasing in size.

Explosive population growth: is often followed by members of the population committing suicide. is rarer in nature than logistic population growth. can lead to a population exceeding its carrying capacity. can continue unchecked, as long as food and shelter are available. is seen more often in nature than logistic growth patterns.

is rarer in nature than logistic population growth.

A life table: indicates the exact year an individual will die and also the cause of death. indicates how many individuals are likely to be born in a population at any given time. is used to determine an individual's likelihood of dying at any given year. is used to determine when a demographic shift is likely to occur in population. indicates which species are likely to go extinct in the near future.

is used to determine an individual's likelihood of dying at any given year.

Which describes a species with a type II survivorship curve? provides no parental care to offspring produces very few offspring high survivability until old age survivorship low at early age likelihood of dying the same at any age interval

likelihood of dying the same at any age interval

A population with an S-shaped growth curve is said to exhibit _____________ growth. exponential density-dependent biotic potential positive logistic

logistic

The "demographic transition" seen in human populations ultimately results in: high birth rates and low death rates. low birth rates and low death rates. no births and no deaths. low birth rate and high death rates. high birth rates and high death rates.

low birth rates and low death rates.

The death rate of organisms in a population exhibiting a type 3 survivorship curve is: higher in post-reproductive than in pre-reproductive years. more or less constant throughout their lives. lower after the organisms survive to the critical age of establishment. usually correlated with density-independent causes. unrelated to age.

lower after the organisms survive to the critical age of establishment.

The death rate of organisms in a population exhibiting a type 3 survivorship curve is: more or less constant throughout their lives. usually correlated with density-independent causes. lower after the organisms survive to the critical age of establishment. higher in post-reproductive than in pre-reproductive years. unrelated to age.

lower after the organisms survive to the critical age of establishment.

As population size increases, the individuals within the population generally experience all of the following except: increased predation risk. increased incidence of disease. diminished accessibility to places to live. reduced food supply. more difficulty in finding mates.

more difficulty in finding mates.

A _____ is a group of individual organisms that have the potential to interbreed with one another. ecosystem population species community demographic

population

Ecology is primarily studied at the _____ level or higher. community ecosystem individual population biome

population

At carrying capacity: a population's growth rate begins to decline. population growth fluctuates around zero. a population's death rate rapidly increases. purely abiotic factors prevent further population growth. birth rate becomes zero.

population growth fluctuates around zero.

A life table: shows the current birth and death rates of an entire population. predicts survival and mortality rates for an individual at a given age. reflects the number of individuals in various age groups in a population at a given time. predicts survivorship, but it cannot accurately predict mortality rate. can be used to construct a population pyramid.

predicts survival and mortality rates for an individual at a given age.

Which represents the per capita growth rate of a population? K r ((K - N)/K) There is no equation for the growth rate of a population; it is visually represented by the logistic growth curve. r x N x K

r

An "age pyramid": shows the current birth and death rates of a population. directly predicts future age distributions of the population. reflects the number of individuals in various age groups in a population. predicts survival and mortality rates for an individual at a given age. is rarely ever shaped like a pyramid.

reflects the number of individuals in various age groups in a population.

Which is a trade-off in life history strategies? reproduction, survival, growth, size of offspring, number of offspring, and parental investment number of offspring and amount of parental investment number and size of offspring reproduction and growth reproduction and survival

reproduction, survival, growth, size of offspring, number of offspring, and parental investment

Which is NOT a mechanism by which humans have so far avoided growth beyond their carrying capacity? the ability to live in higher densities than before the ability to expand into new habitats the ability to manage increased waste production and risk from infectious disease the ability to produce more food than previously possible the ability to use less resources, such as fuel

the ability to use less resources, such as fuel

A life table is to a survivorship curve as: a tire is to a car. the census is to a graph of the country's population. a book is to a page. a car is to a tire. a graph of the country's population is to the census.

the census is to a graph of the country's population.

The physiological breakdowns that we experience as we age are the result of: natural selection selecting against alleles that cause death after sexual maturity. poor lifestyle choices, such as smoking or heavy drinking, early in life. producing too many offspring after maturity, thereby "giving away" one's alleles for longevity. the cumulative effects of the buildup of late-acting mutant alleles in our genomes. not producing any offspring after maturity and, therefore, not passing along alleles for longevity.

the cumulative effects of the buildup of late-acting mutant alleles in our genomes.

In a population, as N approaches K, the logistic growth equation predicts that: the carrying capacity of the environment will increase. the growth rate will approach zero. the population will become monophyletic. the population size will increase exponentially. the growth rate will not change.

the growth rate will approach zero.

What is the LEAST likely explanation for a predator species with no natural predators of its own to experience cyclical spikes and declines in its population. higher populations of the predator reduce prey numbers, leading to a reduction in the predator population, which then repeats as prey numbers recover the predator reaching the carrying capacity of its environment seasonal forest fires that regularly kill a portion of the population contagious disease that spreads whenever the population density increases, causing a population loss mostly among the young or elderly human hunting seasons of the predator for sport, meat, and fur following maximum sustainable yield practices

the predator reaching the carrying capacity of its environment

Ecology is best defined as the study of: the relationships between all living organisms and their environments. the relationships between parasites and their hosts. the preservation of habitats. interactions between predator and prey populations. aquatic organisms.

the relationships between all living organisms and their environments.

Define "ecology." the study of heredity and variation of inherited traits the study of the physical history and structure of the earth the study of the interactions between organisms and their environments the study of plants the study of living organisms and their parts

the study of the interactions between organisms and their environments

A primary difference in the age pyramids of industrialized versus third-world countries is that: in third-world countries, the few who survive childhood live to a very old age. third-world countries show a characteristic "bulge" that indicates a baby boom. third-world countries have significantly more individuals than industrialized countries. third-world countries have much larger proportions of their population in the youngest age group. mean longevity is significantly greater among third-world countries.

third-world countries have much larger proportions of their population in the youngest age group.

"In general, there is a positive correlation between body size and generation time." This statement is: true; larger animals tend to have a longer generation time. false; there is no correlation between body size and generation time. false; however, there is a correlation between body size and type of survivorship curve. true; however, after reaching a certain body size, this correlation levels off. false; there is a negative correlation.

true; larger animals tend to have a longer generation time.

In general, a positive correlation exists between body size and generation time. This statement is: false; the correlation is between small body size and longer generation time. true; larger animals tend to have a longer generation time. true; larger animals tend to have fewer offspring. false; however, a correlation exists between body size and type of survivorship curve. true; however, after reaching a certain body size, this correlation levels off.

true; larger animals tend to have a longer generation time.

Which survivorship curve type is INCORRECTLY matched to its description and/or characteristic organism? type III: high mortality early in life, but those that survive the early years live long lives: mackerel type II: survivorship decreases at a steady, regular pace: common kingfisher type I: high survivorship until old age: giant tortoise type II: survivorship decreases at a steady, regular pace: squirrel. type I: tend to produce a large amount of offspring with little investment: frogs

type I: tend to produce a large amount of offspring with little investment: frogs

The term [(K-N)/K] influences a population growth curve such that: when K is small, mortality rates are lowest. when N equals K, population growth is zero. as N approaches K, the birthrate approaches zero. the increase in actual population numbers is greatest when N is small. as K overtakes K, a population's biotic potential decreases.

when N equals K, population growth is zero.