Ap Bio Unit 8 MCQ #3

To recycle nutrients, an ecosystem must have, at a minimum,

producers and decomposers.

To measure the population of lake trout in a 250-hectare lake, 400 individual trout were netted and marked with a fin clip, then returned to the lake. The next week, the lake was netted again, and out of the 200 lake trout that were caught, 50 had fin clips. Using the mark-recapture estimate, the lake trout population size could be closest to which of the following?

1600

As you study two closely related predatory insect species, the two-spot and the three-spot avenger beetles, you notice that each species seeks prey at dawn in areas without the other species. However, where their ranges overlap, the two-spot avenger beetle hunts at night and the three-spot hunts in the morning. When you bring them into the laboratory and isolate the two different species, you discover that the offspring of both species are found to be nocturnal. You have discovered an example of

resource partitioning.

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?

parasitism

Why is territoriality an adaptive behavior for songbirds maintaining populations at or near their carrying capacity?

Songbird males defend territories commensurate with the size from which they can derive adequate resources for themselves, their mate, and their chicks

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

I and II only

Which of the following is an example of cryptic coloration?

a "walking stick" insect that resembles a twig

A population of white-footed mice becomes severely overpopulated in a habitat that has been disturbed by human activity. Sometimes intrinsic factors cause the population to increase in mortality and lower reproduction rates to occur in reaction to the stress of overpopulation. Which of the following is an example of intrinsic population control?

Females undergo hormonal changes that delay sexual maturation and many individuals suffer depressed immune systems and die due to the stress of overpopulation.

Generally speaking, deserts are located in places where air masses are usually

descending

The major role of detritivores in ecosystems is to

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

Which of the following statements is correct about biogeochemical cycling?

The phosphorus cycle involves the weathering of rocks.

Which of the following levels of ecological organization is arranged in the correct sequence from most to least inclusive?

ecosystem, community, population, individual

The growing season would generally be shortest in which of the following biomes?

northern coniferous forest

Why is a pathogen generally more virulent in a new habitat?

Pathogens evolve more efficient forms of reproduction in new environments.

Photosynthetic organisms are unique to most ecosystems because they

use light energy to synthesize organic compounds.

There are more species in tropical areas than in places more distant from the equator. This is probably a result of

more intense annual solar radiation.

Why do moderate levels of disturbance result in an increase in community diversity?

Habitats are opened up for less competitive species.

Why do logged tropical rain forest soils typically have nutrient-poor soils?

Most of the nutrients in the ecosystem are removed in the harvested timber.

Why is net primary production (NPP) a more useful measurement to an ecosystem ecologist than gross primary production (GPP)?

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

Consider two forests: one is an undisturbed old-growth forest, while the other has recently been logged. In which forest are species likely to experience exponential growth, and why?

Logged, because the disturbed forest affords more resources for increased specific populations to grow.

Which of the following events might you predict to occur if the tilt of Earth's axis relative to its plane of orbit was increased to 33 1/2 degrees?

Summers and winters in the United States would likely become warmer and colder, respectively.

Which of the following is responsible for the differences in summer and winter temperature stratification of deep temperate zone lakes?

Water is densest at 4°C.

What is the primary limiting factor for aquatic productivity?

lack of nutrients

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?

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

Which of the following causes populations to shift most quickly from an exponential to a logistic population growth?

removal of predators

Which of the following statements is consistent with the principle of competitive exclusion?

Even a slight reproductive advantage will eventually lead to the elimination of the less well adapted of two competing species.

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.

40

Invasive species are introduced by humans to new geographic locations and

All of the choices are correct.

Which of the following choices includes all of the others in creating global terrestrial climates?

differential heating of Earth's surface

"Within two years of when zebra mussels were first noticed in the great lakes, they had spread to all five of the great lakes. Their success was thought to be largely due to the fact that their very small larvae were highly adapted for long-distance dispersal"

By the above description, we could describe zebra mussels as _______

r-selected

Which of the following correctly describes exponential population growth?

I. It is population growth that happens as the population nears carry capacity
II. The growth rate of the population will be greater the larger the population size
III. It is more common when population size is small relative to resource size
IV. dN/dt=rN

II, III, and IV

The equation dN/dt=rN[(K-N)/K] describes a

I. "S-shaped" growth curve
II. "J-shaped" exponential growth curve
III. Population whose size is regulated by density-dependent factors
IV. Population whose growth rate decreases as its size approaches K

I, III, and IV only

Which of the following is the most important assumption for the mark-recapture method to estimate the size of wildlife population?

Marked individuals have the same probability of being recaptured as unmarked individuals during the recapture phase

Octopuses can lay hundreds of thousands of eggs at one time. Females will guard the eggs for the month incubation, and do not hunt for food during this time. Upon hatching the female is generally too weak to defend herself from predators and dies within a short period of time. Based on this description, female octopuses are

Semelparous (birth one time then DIE)

As population size (N) approaches the carrying capacity (K) for a certain population, the logistic equation dN/dt=rN[(K-N/K)] predicts that the population

Growth rate will approach zero

Looking at the data in the figure above, what can be said about survival and clutch size?

Large clutch size correlates with low survival

Given that fertility rate is defined as each woman producing exactly enough offspring to replace herself and her offspring's father, if the fertility rate is sustained for a generation, then _______

r=0

A population of ground squirrels has an annual per capita rate of 0.06 and an annual per capita death rate of 0.02. Calculate an estimate of the total number of individuals added to (or lost from) a population of 1000 individuals in one year.

40 individuals added


60 born
-20 die
=40 added

Which of the following best predicts the effect of wildfires on yellow-billed cuckoo populations?

The yellow-billed cuckoo population will decline because the cicadas will emerge before the hatching season.

There is strong evidence that two species of cliff-dwelling birds have nested in the same environment and fed in the same water for thousands of years, with each having stable population sizes. Based on this information which of the following statements is the best conclusion?

The two birds have different ecological niches that allow coexistence.

Which of the following is an example of an ecosystem?

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

Which of the following statements about how honeybees communicate that position of flower patches is most consistent with the model?

The farther the target flowers from the hive, the longer the waggle phase.

Which of the following statements correctly describes a typical trend during the initial stages of succession in a terrestrial ecosystem?

Diversity of plant species increases.

In a tide pool, 15 species of invertebrates were reduced to 8 after one species was removed. The species removed was most likely a(n)

keystone species

Which of the following human actions is most likely to improve the long-term survival of the amphibians?

Building ponds in the areas of dry land to promote interbreeding between the separated populations.

Approximately how many kg of secondary consumer biomass can be supported by a field plot containing 1,000 kg of plant material?

10

Which of the following best explains the observed difference in mass between grass in section I after 14 days and the grass in section III after 21 days?

Mass lost by cell respiration in section III was not replaced by photosynthesis.

Which of the following are important biotic factors that can affect the structure and organization of biological communities?

predation, competition

What is the primary limiting factor for aquatic productivity?

Lack of nutrients

Observations of which of the following locations is most likely to provide useful evidence for Barbara to cite?

A healthy temperate forest ecosystem a few years after a wildfire

which of the following best explains the behavior of the guard squirrels?

The behavior of the guard squirrels increases the survival of close relatives that share the genes of the guard squirrels

A group of biologists were investigating the effects of light color on phototropism in tomato plants. Which of the following correctly identifies the dependent and the independent variables in this experiment?

The percentage of plants showing phototropism is the dependent variable, and the color of the light is the independent variable.

In ecosystems, why is the term cycling used to describe the transfer of chemical elements, whereas the term flow is used for energy exchange?

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

At which labeled point in the graph is the population growth the highest?

III

A scientist is evaluating the proposal for raising large numbers of fish in ocean pens for human consumption. Which of the following is the most appropriate factor to use as the dependent variables in the experimental investigation?

The amount of metabolic wastes in the water where the fish are being raised.

Biodiversity is important to humans because

All of these are correct

Which of the following predicts the most likely ecological problem that would occur if the guppies are introduced into new areas to control the mosquito population?

The guppies might have no natural predators, which will result in dramatic increase in the guppy population and an increase in competition for other native species.

In the process of succession, which of the following is true of K-selected species?

They are dominant species in the early stages of succession

Which of the following best predicts the results of a drought in the savanna research area with regards to community resilience to this environmental change?

The lightly grazed area is likely to recover more quickly from the drought due to greater biodiversity.

The diagram above shows the progression of ecological events after a fire in a particular ecosystem. Based on the diagram, which of the following best explains why the oak trees are later replaced by other trees?

Eventually the other trees grow taller that the oak trees and form a dense canopy that shades the understory.

Climate change is currently having the greatest impact in which biomes?

Arctic biomes

All of the following are density-dependent factors that limit animal populations EXCEPT

weather

A fish population of 250 in a pond has a max annual rate of increase of 0.8. If the carrying capacity of the pond is 1,500 for this species, what is the expected population size after one year?

417

What would the population size of the sika deer be one year after the carrying capacity increase to 70,000 as a result of deforestation? Assume rmax does not change.

The population would grow to 63,667 deer in a year, and the growth rate would decrease the following year.

The purple sea star is an example of...

Keystone species

Many developing countries are becoming overpopulated which puts stress on local ecosystems. Many of these ecosystems are destroyed and cause a depletion of natural resources such as food. Which of the following would be the best solution to this problem?

Empower and educate women

Plastics in the ocean is very harmful to many living things. Which of the following would be the best solution to this problem?

- Local governments ban the use of plastics in the sale of beverages and food products
- Launch a local campaign to ensure all plastics are recycled
- Get groups together to pick up trash out of the ocean

Why do moderate levels of disturbance result in an increase in community diversity?

Habitats are opened up for less competitive species.