Ecology Exam Practice

In a community, autotrophs generate 1,000 calories per hour of GPP and 500 calories per hour of NPP. Primary consumers convert 10 calories per hour into their own biomass. What is the ecological efficiency in the link between autotrophs and primary consumers in this community? 1 percent 2 percent 20 percent 10 percent

2 percent

The GPP of a community is 40 units per day on average, while the NPP of the community is 15 units per day. How many units are used for cellular respiration and other catabolic processes of the plants? 0 15 25 40 55

25

How long will it take a population of 550 moose to double if 25 offspring are born and 14 moose die on average per year? 34.5 years 52.3 years 26.9 years 79.0 years

34.5 years

All of the following are true for a population with logistic growth EXCEPT: r is constant r is maximized at 1/2K r is low when very close to K

A

The NPP of a community is 150 units per month and the GPP is 240 units per month. If the ecological efficiency of herbivores is 1/6, how many units of plant biomass are converted into biomass of herbivores? 25 40 150 900 1,440

A

The theory of island biogeography states that the rate at which new species arrive on an island increases with closeness to the mainland. decreases with closeness to larger islands. increases as more species occupy the island. is lower than the extinction rate at the equilibrium species richness. is greater than zero when all species on the mainland are present on the island.

A

What factor is responsible for the difference in ecological efficiency between grassland and forest ecosystem? consumption efficiency assimilation efficiency production efficiency

A

How are humans influencing the carbon cycle? Through changes in land use, which increase the atmospheric pools of CO2 and CH4 By cutting forests and burning biomass, which increase the atmospheric pool of CO2 By burning fossil fuels and manufacturing cement, which increase the atmospheric pool of CO2 All of the above

All of the above

How are humans influencing the nitrogen cycle? By increasing the rate of nitrogen fixation through industrial processes and intensive agriculture By increasing the production of oxides of nitrogen and other chemical forms through burning fossil fuels and biomass By increasing the production of oxides of nitrogen and other chemical forms through livestock production and some forms of agriculture All of the above

All of the above

Which of the following statements about air is correct? As air rises, it expands and becomes warmer. As air rises, it contracts and becomes cooler. As air falls, it contracts and becomes warmer. As air falls, it expands and becomes warmer.

As air falls, it contracts and becomes warmer.

Complete the following sentence. when orcas started eating sea otters, the sea otter population ___________________, the urchin population ______________________, and the kelp population _____________________________. Decreased, decreased, decreased Decreased, increased, decreased Increased, decreased, increased Increased, increased, increased

B

Per capita rate of increase (r) will always increase when: birth rates and death rates increase birth rates increase and death rates decrease birth rates and death rates decrease birth rates decrease and death rates increase

B

To maximize net primary productivity, the best combination of climatic conditions is high temperature and high precipitation. high temperature and medium precipitation. high temperature and low precipitation. medium temperature and high precipitation. medium temperature and medium precipitation

B

Usually, there is _______ precipitation on the windward than the leeward side of a mountain range. In the middle latitudes of the Northern Hemisphere, this means that _______ sides of mountains receive more precipitation. more; eastern more; western less; northern less; eastern less; western

B

What is the outcome of competition between two species when intraspecific competition is stronger than interspecific competition for both species 1 and species 2? Species 1 outcompetes Species 2 Species 2 outcompetes Species 1 Both species co-exist in stable equilibrium One species outcompetes the other.

Both species co-exist in stable equilibrium

A technique called random sampling can be used to estimate population size. Using this method, the organisms within a subset of the areas that a population inhabits are counted, and population abundance is extrapolated for the entire region in which the population is found. For instance, if a biologist counts 10 squirrels living in a 200-square foot area, she or he could predict that there are 100 squirrels living in a 2000 square foot area. This is a simple ratio. A biologist collected 50 liters of pond water and counted 10 mosquito larvae. How many larvae would you estimate to be in that pond if the total volume of water in the pond was 80,000 liters? 8000 10000 16000 32000 12000

C

All of these factors reduce the efficiency of energy transfer between trophic levels except: heat loss due to maintaining homeostasis. indigestibility of some biomass. biomass stored as fat or starch. lack of availability of some biomass.

C

For a population at carrying capacity (K): The birth rate of the population is equal to 0 The death rate of the population is equal to 0 The birth rate and death rate are equal to each other None of the above.

C

Ice core data show the average global temperature: was much cooler than it is today. was much warmer than it is today. fluctuated quite a bit, correlated with changes in atmospheric CO2. fluctuated quite a bit, independent of changes in atmospheric CO2.

C

If humans eat the grain directly instead of eating the cows, how much grain is required to produce 70 kg of human biomass (assuming ecological transfer efficiency is 10%)? 7 kg 70 kg 700 kg 7,000 kg 70,000 kg

C

If, over a long period of time, a region that is currently in the temperate seasonal forest biome becomes considerably colder, this region will most likely become temperate rain forest. savanna. boreal forest. tropical rain forest. subtropical desert.

C

In a density dependent population, per capita growth rate (r) ___________ as the population size approaches carrying capacity (K). stays the same increases decreases

C

Over land, precipitation is _______ evaporation, and over oceans, precipitation is _______ evaporation. greater than; greater than greater than; equal to greater than; less than less than; greater than less than; equal to

C

A cosmic catastrophe jolts Earth so that its axis is perpendicular to the orbital plane between Earth and the sun. The LARGEST effect of this change would be Elimination of tides Increase in length of night at equator Decreased temperature at equator Elimination of seasonal variation

D

All of the following statements about habitat fragmentation are true EXCEPT: Small isolated patches lose species more rapidly than larger, isolated patches. Isolated patches lose species more rapidly than patches of similar size that are near other patches. Habitat fragmentation results in lower species richness in the fragments than in the original habitat. Human-altered habitat surrounding patches increases the colonization rate of patches. Connecting fragments with dispersal corridors enhances colonization.

D

An ecologist wants to know how many leopard frogs inhabit a small pond in her neighborhood. She captures 100 leopard frogs from around the pond after a rainstorm, marks them with a non-toxic permanent elastomer tattoo and releases them alive and well. A week later, she captures 400 leopard frogs in and around the pond and finds that 50 of the 400 frogs captured have colored tattoos. What is the estimated population size, based on recovery of marked frogs? Population size estimate = (number captured x number originally marked)/number captured with mark 1200 400 2000 800 600

D

Based on the principles of island biogeography, one practical step restoration ecologists could take to limit the negative effects of fragmentation is to leave dispersal corridors. A second step is to decrease colonization. decrease average patch size. remove nonessential species from patches. keep average patch size as large as possible. keep patches as far from each other as possible

D

Earth acts as a(n) _______ system in terms of materials and a(n) _______ system in terms of energy. open; open open; closed open; recycling closed; open closed; recycling

D

Grain is eaten by cows, and cows are eaten by humans. If the ecological transfer efficiency between each trophic level is 10 percent, how much grain is required to produce 70 kg of human biomass? 7 kg 70 kg 700 kg 7,000 kg 70,000 kg

D

Net primary productivity (NPP) of a community is approximately equivalent to gross primary productivity (GPP). energy used in respiration per unit time. energy captured by plants from sunlight per unit time. gross primary productivity (GPP) minus respiration (R). gross primary productivity (GPP) plus respiration (R).

D

Which flux removes the most carbon per year from the atmosphere? outgassing dissolution respiration photosynthesis soils

D

Which pool stores the most Nitrogen? Soils Ocean Rock Atmosphere Plants

D

Which of the following is NOT an example of a consumer-resource interaction? A.Predation . B.Disease . C.Herbivory . D.Competition

D.Competition

What is meant by the term "doubling time" and how did changing values for N0 affect the doubling time of a population? Doubling time is the amount of time needed for a population to double in size; increasing N0 did not change the doubling time . Doubling time is the time needed for an individual in the population to reproduce itself; increasing N0 decreased the doubling time. Doubling time is the amount of time needed for a population to double in size; increasing N0 increased the doubling time. Doubling time is the time needed for an individual in the population to reproduce itself; increasing N0 did not change the doubling time.

Doubling time is the amount of time needed for a population to double in size; increasing N0 did not change the doubling time

What form of radiation is absorbed by Earth's surface and atmosphere, and what form does this radiation take when it eventually moves off into space? Earth absorbs long-wave visible and ultraviolet radiation and emits short-wave infrared radiation. Earth absorbs short-wave visible and ultraviolet radiation and emits long-wave infrared radiation. Earth absorbs short-wave infrared radiation and emits long-wave visible and ultraviolet radiation. Earth absorbs long-wave infrared radiation and emits short-wave visible and ultraviolet radiation

Earth absorbs short-wave visible and ultraviolet radiation and emits long-wave infrared radiation.

The Cascade Mountains bisect the state of Washington into western and eastern portions. The western portion is bounded on its western border by the Pacific Ocean. The eastern portion is bounded on its eastern border by the state of Idaho. What might you predict about these two portions based on the information presented in the tutorial? Eastern Washington has more vegetation than western Washington. Eastern Washington is wetter than western Washington. Eastern Washington has a higher proportion of drought-resistant vegetation than western Washington. Eastern Washington is more humid than western Washington.

Eastern Washington has a higher proportion of drought-resistant vegetation than western Washington.

Sort the steps of the Hadley cell in the correct order. Clouds form. Incoming solar radiation hits Earth's surface. Cool air descends. Warm air rises.

First - Incoming solar radiation hits Earth's surface. Second - Warm air rises. Third - Clouds form. Fourth - Cool air descends.

Which carbon reservoir experienced the greatest change (in amount) from the pre-industrial period to the contemporary period? Land Ocean Atmosphere Fossil Fuels

Fossil Fuels

Which of the following is the major compartment for carbon in Earth's system? Atmospheric CO2 Fossil fuels Dissolved CO2 in oceans Living biomass

Fossil fuels

How do greenhouse gases and aerosols in the atmosphere affect Earth's radiation budget? Greenhouse gases increase the trapping of infrared radiation emitted by Earth, and aerosols decrease the amount of solar radiation that reaches Earth's atmosphere. Both decrease the trapping of infrared radiation emitted by Earth. Both increase the trapping of infrared radiation emitted by Earth. Greenhouse gases increase the trapping of infrared radiation emitted by Earth and aerosols increase the amount of solar radiation that reaches Earth's atmosphere.

Greenhouse gases increase the trapping of infrared radiation emitted by Earth, and aerosols decrease the amount of solar radiation that reaches Earth's atmosphere.

Which of the following statements about ecological transitions is true? It occurs rapidly enough that traces of its earliest stages are quickly lost. It leads to a community distinctly different from the original community. It leads to a community resembling the original community. It occurs slowly enough that traces of its earliest stages are difficult to find.

It leads to a community distinctly different from the original community.

Which pathway represents the shortest path that a nitrogen atom in atmospheric nitrogen, N2, could travel and end up in a protein in a human? N2 → human N2 → bacterium → plant → human N2 → bacterium → animal → human N2 → bacterium → human

N2 → bacterium → plant → human

Which of the following is an outcome of interspecific competition? Both species coexist at population densities greater than would be present if they existed in the same environment without the other. Only one species survives; the other goes extinct. Both species grow at greater rates than would occur if they were present in the same environment without the other. All of the above

Only one species survives; the other goes extinct.

How do changing values for r affect the growth rate of a population? Populations grow when r is negative, remain constant when r is zero, and shrink when r is positive. Populations grow when r is negative, remain constant when r is positive, and shrink when r is zero. Populations grow when r is positive, remain constant when r is zero, and shrink when r is negative. Populations grow when r is positive, remain constant when r is negative, and shrink when r is zero

Populations grow when r is positive, remain constant when r is zero, and shrink when r is negative.

Which of the following adaptations would be most likely found in organisms that live in the tundra biome? C4 photosynthesis A taproot Large thin leaves Ectothermy Production of antifreeze proteins

Production of antifreeze proteins

Which of these does not help explain why food chains have low levels of ecological efficiency? Animals at each trophic level do not ingest all the biomass available . Some ingested food is used to fuel metabolic processes and is lost as heat. Some ingested food is used in growth and reproduction. Some digested food cannot be ingested and becomes waste. Primary producers cannot capture all of the energy available from the sun.

Some ingested food is used in growth and reproduction.

Which statement(s) is an example of climate? (Check all that apply.) The high for today in Gainesville, FL will be 66°F. The average temperature in Gainesville during the month of July, calculated between 1981-2010, is 91°F. On January 28, 2014, Pensacola, FL received 1.8 inches of snow.

The average temperature in Gainesville during the month of July, calculated between 1981-2010, is 91°F.

Which of the following is NOT true about fossil fuels? Fossil fuels are a non-renewable resource Carbon emissions from fossil fuels have increased since the pre-industrial period. The land and oceans are able to absorb all of the C emitted to the atmosphere by fossil fuels. Carbon from fossil fuels comes from dead organisms that have been buried for millions of years. Prior to the industrial revolution carbon in the fossil fuels reservoir was not exchanging with the atmosphere

The land and oceans are able to absorb all of the C emitted to the atmosphere by fossil fuels.

What is carrying capacity? The resources needed to support a particular population The area of land capable of supporting a particular population The minimum size of a population necessary for ensuring that it can continue into the future The number of individuals in a population that can be supported by an area

The number of individuals in a population that can be supported by an area

Given the scenario in the previous question, what do you predict the population of the plants that the rabbits eat will do over time, in response to this change in the biotic environment? The plant population will decrease, due to the increased rabbit population. The plant population will decrease, due to the decreased rabbit population. The plant population will increase, due to the decreased rabbit population. The plant population will neither increase nor decrease.

The plant population will increase, due to the decreased rabbit population.

How would your predicted response in the previous question likely affect populations of other herbivores that gave little to no interaction with foxes or wolves? (Assume that these herbivores eat the same types of plant as the rabbits do.) The population of other herbivores will decrease, due to the decreased plant population. The population of other herbivores will neither increase nor decrease. The population of other herbivores will increase, due to the increased plant population. The population of other herbivores will increase, due to the decreased plant population

The population of other herbivores will increase, due to the increased plant population.

If the size of a population is greater than the carrying capacity (K), what will happen to the population? The population size will increase. The population size will not change. The population will experience no births. The population will experience more deaths than births.

The population will experience more deaths than births.

A species of rabbit is preyed upon by foxes, which are preyed upon by wolves. Humans decide to open a hunting season on the wolf population. What do you predict will happen to the rabbit population over time in response to this change in the biotic environment? The rabbit population will neither increase nor decrease. The rabbit population will decrease, due to the increased fox population. The rabbit population will increase, due to the increased fox population. The rabbit population will decrease, due to the decreased fox population.

The rabbit population will decrease, due to the increased fox population.

A student remarks that it is a good thing that humans discovered how to use industrial processes to fix nitrogen because this ensures that the nitrogen cycle can remain intact if nitrogen-fixing bacteria ever go extinct. Evaluate the accuracy of this statement. The statement is inaccurate because the product of nitrogen fixation through industrial processes does not have the same biological properties as the product of nitrogen fixation by bacteria. The statement is accurate because humans are able to fix nitrogen on a large scale that rivals the rate of the process carried out by bacteria. The statement is accurate because nitrogen-fixing bacteria are the only living things that can fix nitrogen through biochemical pathways, and their loss would be devastating. The statement is inaccurate because humans would not be able to distribute the product of nitrogen fixation from industrial processes in the same way that bacteria are able to distribute it globally now.

The statement is inaccurate because humans would not be able to distribute the product of nitrogen fixation from industrial processes in the same way that bacteria are able to distribute it globally now.

By what process does nitrogen enter the living components of ecosystems? By human-made industrial processes Through fixation by microbes By ingestion of plants or other primary producers whose tissues contain protein and other organic molecules that themselves contain nitrogen Absorbed as nitrogen gas from the atmosphere

Through fixation by microbes

Warm temperatures that vary little across the year and a distinct dry season are characteristics of which biome? Tropical Rainforest Tropical savanna/ Seasonal forest Temperate grassland Tundra Boreal Forest

Tropical savanna/ Seasonal forest

What flux(es) can be contributed to anthropogenic activity? a)Altered land use and Fossil fuel burning b)Biomass Burning c)Outgassing d)All of the above e)A, B

e)A, B

Precipitation tends to be _______ on the _______ side of a mountain because water vapor _______ as it rises there. higher; windward; condenses higher; leeward; expands lower; leeward; condenses lower; windward; expands

higher; windward; condenses