Ecology Exam 2

Among the array of species that make up a community, not all are equally abundant. A. True B. False

A. True

Ecologists use a variety of useful sampling and statistical techniques for delineating and classifying communities. A. True B. False

A. True

In mutualism, the interaction between two species is more often a reciprocal exploitation than a cooperative effort between individuals. A. True B. False

A. True

In the Lotka-Volterra models of predatory interactions, prey density does not influence predatory mortality. A. True B. False

A. True

Indirect interactions can either be positive or negative for the affected species. A. True B. False

A. True

Most predator populations grow slowly in comparison to those of their prey. A. True B. False

A. True

Nectar is often produced by plants as an enticement or reward for pollinating animals. A. True B. False

A. True

Some plants are able to attract beneficial insects that act to deter herbivory on that plant. A. True B. False

A. True

The relationship between ants and acadias represents a defensive mutualism. A. True B. False

A. True

The theory of island biogeography was developed for islands and cannot be applied to habitat patches within a larger landscape.

A. True B. False

Which of the following is the least major agent of disturbance? A. a rainstorm B. fire C. flooding D. a beaver constructing a dam

A. a rainstorm

Which statement best describes a keystone species? A. a rare or uncommon species that has a strong effect on its community B. an abundant species that may or may not affect other species C. a common species that has a strong effect on its community D. a species that takes up a great deal of space in a community.

A. a rare or uncommon species that has a strong effect on its community

Which of the following is not a class of plant secondary compounds?

A. alkanes

In a forest community, the layer in which most photosynthesis occurs is the A. canopy B. understory C. forest floor D. midstory

A. canopy

Microparasites are usually characterized by A. direct transmission from one host to another. B. a long generation time. C. a long time of infection relative to the host's expected life span. D. a large body size.

A. direct transmission from one host to another.

In a rank-abundance curve comparing two communities, the community with the greater species richness is characterized by a A. greater length of the curve and a more gradual slope B. greater length of the curve and a steeper slope C. lesser length of the curve and a more gradual slope D. lesser length of the curve and a steeper slope.

A. greater length of the curve and a more gradual slope.

Which of the following is a positive numerical response made by a predator in response to an increase in prey density? A. immigration of predators to an area of high prey density B. decrease in predator reproduction rate C. increase in predator survival rate D. decrease in predator mortality rate

A. immigration of predators to an area of high prey density

While foraging on grass, white-tailed deer occasionally ingest snails or slugs that host larvae of the meningeal worm. The worm larvae mature inside the deer and eventually are passed out with the feces. The snails acquire the larvae as they come into contact with deer feces on the ground. The snails are an example of a(n) A. intermediate host B. direct host C. macrohost D. definitive host

A. intermediate host

The net outcome of predator-prey interactions in the basic Lotka-Volterra models is that A. predator and prey populations oscillate, which each predictably increasing and decreasing in response to the other. B. the prey population declines and this causes the predator population to also decline. C. the predator drives its prey to extinction and then goes extinct itself. D. predator and prey populations eventually converge on equilibrium population sizes that are maintained into infinity.

A. predator and prey populations oscillate, with each predictably increasing and decreasing in response to the other.

The intimate and protracted association between two or more organisms of different species is referred to as A. symbiosis B. parasitism C. commensalism D. mutualism

A. symbiosis

The inhibition model of succession proposes that A. the first species to arrive make the site less suitable for later arriving species. B. early successional species modify the environment s that is becomes more suitable for later successional species. C. later successional species are neither inhibited nor aided by species of earlier stages. D. competition does not occur between early successional and late successional species.

A. the first species to arrive make the site less suitable for later arriving species.

Habitat fragmentation is harmful because no species are adapted to living along habitat edges. A. True B. False

B. False

In the Lotka-Volterra equations that represent predator-prey interactions, predators are a source of density-independent mortality for prey. A. True B. False

B. False

Parasites always complete their life cycle in a single host species. A. True B. False

B. False

Quantitative inhibitors in plants toxic secondary compounds, often causing herbivores to avoid their consumption.

B. False

Succession usually involves only autotrophic species such as plants. A. True B. False

B. False

The removal of a keystone species from a community typically results in an increase of biodiversity. A. True B. False

B. False

The size and shape of habitat patches are determined more by the activities of animals than by the interaction of geology, topography, and climate. A. True B. False

B. False

Which of the following statements is true? A. Large patches of habitat usually contain fewer species than small patches. B. Large animals usually have larger home ranges than smaller animals. C. Small species are usually limited to small habitat patches. D. Carnivore home ranges are usually smaller than herbivore home ranges.

B. Large animals usually ave larger home ranges than smaller animals.

Plant community structure along an environmental gradient can often be explained by A. differences among species in their competitive abilities. B. a trade-off among species with respect to competitive ability and stress tolerance. C. differences among species into their abilities to tolerate stress. D. differences among species in their resistance to herbivores

B. a trade-off among species with respect to competitive ability and stress tolerance.

In a graph that plots prey population (N prey) on the x-axis against the number of predator offspring produced per unit of time on the y-axis, the slope represents the A. efficiency of predation (c). B. efficiency with which food is converted into predator population growth or reproduction (b). C. predator population growth rate (r). D. the rate of increase in prey availability.

B. efficiency with which food is converted into predator population growth or reproduction (b).

According to the theory of island biogeography, the islands with the most species will be A. large and far from the mainland. B. large and close to the mainland. C. small and close to the mainland. D. small and far from the mainland.

B. large and close to the mainland.

According to the Red Queen hypothesis, A. most predators consume a varied diet in order to meet their nutritional requirements. B. prey must continually evolve means of avoiding capture to avoid extinction. C. natural selection should favor the most efficient foragers. D. the population density of a predator depends on the population density of its prey.

B. prey must continually evolve means of avoiding capture to avoid extinction.

European kestrels feed on Microtus voles, with the "kill" rate defined as the number of prey taken during the breeding season, as linearly proportional to the density of Microfus. This type of functional response is referred to as A. type III B. type I C. type II D. type IV

B. type I

The number of species within a community is usually greatest when A. a low frequency of disturbance occurs. B. no disturbance occurs. C. an intermediate frequency of disturbance occurs. D. a high rate of disturbance occurs.

C. an intermediate frequency of disturbance occurs.

A mutualism in which two species benefit when living together but can survive when apart is referred to as a(n): A. obligatory mutualism B. trophic mutualism C. faculatative mutualism D. dispersive mutualism

C. facultative mutualism

The impact of a disturbance is determined by its A. period, scale, and type. B. frequency, intensity, and strength. C. frequency, intensity, and scale. D. frequency, period, and scale.

C. frequency, intensity, and scale.

Plants adapted to edge environments tend to be A. tolerant of shade and prefer moisture. B. intolerant of shade and prefer moisture. C. intolerant of shade and tolerant of dry conditions.

C. intolerant of shade and tolerant of dry conditions.

Food webs are typically arranged into trophic levels with A. herbivores at the bottom, carnivores in the middle, and primary produces at the top. B. carnivores at the bottom, herbivores in the middle, and primary producers at the top. C. primary producers at the bottom, herbivores in the middle, and carnivores at the top. D. primary producers at the bottom, carnivores in the middle, and herbivores at the top.

C. primary producers at the bottom, herbivores in the middle, and carnivores at the top.

Which of the following is considered a non-lethal effect of predation? A. increased predator mortality B. reduced competition C. reduced activity of prey D. prey consumption

C. reduced activity of prey

Within a landscape mosaic, patches A. typically lack a distinct boundary. B. are composed of relatively heterogeneous. C. tend to vary in shape. D. tend to be similar in size.

C. tend to vary in shape.

Which of the following can be considered a habitat corridor? A. a patch of forest within a city park B. a large lake in a city park C. an abandoned agricultural field in an urban area D. a strip of forest along the banks of a river flowing from a forested mountain through a city

D. a strip of forest along the banks of a river flowing from a forested mountain through a city.

A set of local communities that are linked by the dispersal of multiple, potentially interacting species is referred to as a(n) A. metapopulation B. ecotone C. archipelago D. metacommunity

D. metacommunity

When an ecologist compares the diversity of different communities by counting the number of species within each community, the measure of diversity being used is called A. species diversity B. species evenness C. relative abundance D. species richeness

D. species richness

Changes in community composition and structure over time are called A. zonation B. stratification C. characterization D. succession

D. succession