Biology for AP Courses

Julianne Zedalis, John Eggebrecht

Chapter 35

Ecology and the Biosphere - all with Video Answers

Educators

Chapter Questions

Problem 1

C, H, O and N are nutrients that are cycled through the Earth in different forms. Which of the following levels of ecology will include the study of nutrient cycling though the environment?
a. organismal ecology
b. population ecology
c. community ecology
d. ecosystem ecology

Rikhil M.

Rikhil M.

Numerade Educator

Problem 2

Which of the following are arranged from least inclusive to most inclusive?
a. population>ecosystem>community > biosphere
b. ecosystem < population < biosphere < community
c. biosphere < ecosystem < community < population
d. population < community < ecosystem < biosphere

April T.

Numerade Educator

Problem 3

An ecologist is studying the patterns on the wings of an endangered butterfly species that allow it to escape of __.
a. mimicry
b. organismal ecology
c. mutualism
d. community ecology

Rikhil M.

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Problem 4

Each year, Lake Michigan beach visitors are warned of possible E.coli, which can cause illness. In order to understand how environmental conditions, both biotic and abiotic, affect E. coli risk, which type of individual should an infectious disease specialist collaborate with?
a. an ecosystem ecologist
b. a podiatrist
c. a community ecologist
d. a population ecologist

April T.

Numerade Educator

Problem 5

Some bacterial species can use nitrogen directly from the atmosphere. In this situation, the bacteria are a _____.
a. biotic factor
b. abiotic factor
c. predator
d. symbiotic partner

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Numerade Educator

Problem 6

Photosynthetic organisms are important to most ecosystems because they_____.
a. synthesize organic compounds they obtain from decaying heterotrophs.
b. can use carbon dioxide and sunlight and synthesize their own food.
c. use wind energy to synthesize organic compounds.
d. synthesize inorganic compounds from organic compounds.

April T.

Numerade Educator

Problem 7

The study of population ecology focuses on ___.
a. The number of individuals of one species in an area and how and why that number changes over
time.
b. The processes driving interactions within and among different species within an area.
c. The adaptations that enable individuals to live in specific habitats.
d. Plants and animals living in an enclosed area

Rikhil M.

Numerade Educator

Problem 8

The study of the effect of abiotic factors such as rain and temperature on the distribution of living organisms is known as ___.
a. community ecology
b. biogeography
c. ecosystem
d. geography

April T.

Numerade Educator

Problem 9

Many species of pine trees are found in different geographical locations in North America and Canada. This is because _____.
a. they were not separated geographically over millions of years and did not evolve to be different species.
b. plant breeders carried seeds to different areas.
c. pollen from pollen tree was able to travel far.
d. pine was present widely and in some areas they dried out.

Rikhil M.

Numerade Educator

Problem 10

An ecologist hiking up a mountain may notice different biomes along the way due to changes in all of the
following except ____.
a. elevation
b. rainfall
c. latitude
d. temperature

April T.

Numerade Educator

Problem 11

Temperate forests have plants of varying sizes. Understory plants in a temperate forest have adaptations to capture limited ____.
a. water
b. nutrients
c. heat
d. sunlight

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Problem 12

In which of the following bodies of water does temperature stratification not take place?
a. estuaries
b. lakes
c. seas
d. oceans

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Problem 13

Plants living in deserts have adaptations such as hair on leaves and a thick cuticle. What purpose do these adaptations serve?
a. to conserve water
b. to prevent exposure to sunlight
c. to increase oxygen intake
d. to decrease carbon dioxide intake

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Problem 14

Which of the following biomes would have maximum net primary production?
a. deciduous forests
b. deserts
c. arctic tundra
d. savannas

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Numerade Educator

Problem 15

When the Net Primary Productivity was measured in the presented graph, what was included in those
measurements?
a. Above and underground biomass are included in net primary productivity.
b. Net primary productivity is the total amount of carbon fixed.
c. Net primary productivity is the amount of carbon fixed minus the amount used during cellular respiration and includes only the aboveground biomass in terrestrial biomes.
d. Net primary productivity refers to the amount of total amount of carbon fixed.

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Problem 16

Biogeography is the study of the geographic distribution of living things and the _____ that affect their
distribution.
a. Abiotic factors
b. Biotic factors
c. Biomes
d. Conspecifics

April T.

Numerade Educator

Problem 17

In which of the biomes are plants unable to grow because the soil is frozen most of the year?
a. arctic tundra
b. boreal forests
c. grasslands
d. chapparals

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Numerade Educator

Problem 18

In grasslands, forest fires are a common occurrence. Which of the following statements regarding grasslands is true?
a. They have the ability to withstand fires.
b. They have a well-developed root system, which allows them to regrow after a fire.
c. Grasses are tall and only their top portions are destroyed.
d. Trees shield some of the grass thus protecting it from fire.

April T.

Numerade Educator

Problem 19

Savannas are grasslands with scattered trees. Which statement is correct about savannas?
a. They receive abundant rainfall.
b. The temperatures are cold throughout the year.
c. They have relatively long dry seasons.
d. Savannas are dominated by fluctuations in temperature.

Rikhil M.

Numerade Educator

Problem 20

The boreal forest, also known as taiga or coniferous forest, is found south of the Arctic Circle and across most of Canada, Alaska, Russia, and northern Europe. What are the characteristics of the boreal forest?
a. high temperature
b. deciduous trees
c. high humidity
d. acidic soil

April T.

Numerade Educator

Problem 21

The amount of sunlight and rainfall affects the growing season of plants in different biomes Which of the following biomes is characterized by short growing seasons?
a. savanna
b. temperate grasslands
c. arctic tundra
d. tropical wet forest

Rikhil M.

Numerade Educator

Problem 22

The figure shows different zones present in the ocean. Which of the following statements about marine biomes is true?
a. The benthic zone includes the ocean’s open water and shore.
b. The pelagic realm includes all of the ocean’s open water.
c. The majority of the ocean includes the photic zone.
d. The deepest zone of the ocean is known as the aphotic zone.

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Problem 23

Corals have a mutualistic relationship with photosynthetic algae in the photic zones of water. What
purpose does this serve?
a. Corals are able to derive their nutrition from the algae and thus survive in the nutritionally poor water.
b. Corals are able to accumulate calcium carbonate from the algae.
c. They can form coral reefs because of this association.
d. The corals provide protection to the algae.

Rikhil M.

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Problem 24

Which of the following abiotic factors is most important for sustaining life in marine biomes?
a. wind
b. soil
c. salt
d. warmth

April T.

Numerade Educator

Problem 25

There are several different marine zones. In which zone are organisms exposed to air and sunlight at low tide and are underwater most of the time, especially during high tide?
a. intertidal zone
b. neritic
c. oceanic
d. abyssal

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Problem 26

Which of the following photosynthetic organisms are more likely to grow in a lake as opposed to a river?
a. fungi
b. phytoplankton
c. moss
d. lichens

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Numerade Educator

Problem 27

Water flow can vary in wetlands. Freshwater marshes and swamps are characterized by _____.
a. dry soil
b. rapid water flow
c. slow water flow
d. irregular water flow

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Numerade Educator

Problem 28

Water bodies can differ in the amount of salt present. Which of the following is a characteristic of an estuary?
a. a continuous body of water with high salinity
b. an area where the salinity varies
c. a body of water with low salinity
d. a body of water with low salt entering land

April T.

Numerade Educator

Problem 29

The earth’s geological past has witnessed many important events. Which of the following periods was
associated with global warming?
a. Permian period
b. Cambrian period
c. 2nd and 3rd century BC
d. 20th century

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Problem 30

One of the indirect consequences of global warming has been ___.
a. loss of biodiversity
b. increase in temperature
c. change in water quality
d. increase in temperature tolerance of plants

April T.

Numerade Educator

Problem 31

Which one of the following fuels was used extensively during the Industrial Revolution, leading to increases in levels of carbon dioxide?
a. coal
b. petroleum
c. natural gas
d. solar energy

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Numerade Educator

Problem 32

Global warming is due to many factors. Which of the following is known to change with $\mathrm{CO}_{2}$ concentration?
a. solar intensity
b. wind intensity
c. temperature
d. humidity

April T.

Numerade Educator

Problem 33

All of the following are natural factors have led to slow increases in global temperatures except____.
a. volcanic eruptions
b. change in solar intensity
c. earthquakes
d. changes in the earth’s orbit

Rikhil M.

Numerade Educator

Problem 34

Global temperatures have been steadily increasing since the Industrial Revolution largely as a result of ___.
a. agricultural production
b. burning of fossil fuels
c. increase in movement of people
d. use of pesticides

April T.

Numerade Educator

Problem 35

Which of the following gases is not considered a significant contributor to global warming?
a. carbon dioxide
b. methane
c. nitric oxide
d. oxygen

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Problem 36

Carbon dioxide, methane, and nitrous oxide are considered greenhouse gases because___.
a. They trap solar radiation released from the sun as it reaches the Earth’s surface, similar to the glass in a greenhouse.
b. They are found mostly in green houses.
c. These gases are essential for plant growth in a green house.
d. They trap solar radiation, which is converted into thermal radiation on the Earth’s surface of which some is reradiated back into the atmosphere.

April T.

Numerade Educator

Problem 37

The Medieval Climate Anomaly occurred between 900 and 1300 AD. Temperatures during this time were between 0.10 and 0.20 higher. This allowed _____.
a. the Vikings to colonize Greenland
b. large amounts of new technologies to be invented
c. advances in agriculture
d. harsh winters

Rikhil M.

Numerade Educator

Problem 38

Define and describe community ecology. Give an example
a. It is the study of the number of individuals of one species in an area as well as how and why
the number changes over time. An example would be counting the number of individuals of the Karner blue butterfly, a federally endangered species whose population density is highly influenced by the abundance of wild lupine.
b. It is the study of the processes and consequences of interactions within and among different
species within an area. An example would be the work of scientists who work in a marsh studying
the various interactions of several populations of birds, crabs, and grasses without studying the
water or air quality.
c. It is the study of the physiological, morphological, and behavioral adaptations that enable individuals to live in specific habitats. An example would be the work of scientists who work in a marsh studying the various interactions of several populations of birds, crabs, and grasses without studying the water or air quality.
d. It is the study of the processes and consequences of interactions within and among different
species within an area. An example would be counting the number of individuals of the Karner blue butterfly, a federally endangered species whose population density is highly influenced by the abundance of wild lupine.

April T.

Numerade Educator

Problem 39

Ecologists often collaborate with other researchers interested in ecological questions. Describe the levels of ecology that would be easier for collaboration because of the similarities of questions asked. What levels of ecology might be more difficult for collaboration?
a. It is easier to study community and ecosystem ecology as the effect of biotic and abiotic factors can be studied in a community or ecosystem more easily. Organismal and population ecology
might be more difficult for collaboration.
b. It is easier to study organismal and population ecology as the effect of biotic and abiotic factors
can be studied in an organism or population more easily. Community and ecosystem ecology
might be more difficult for collaboration.
c. It is easier to study community and population ecology as the effect of biotic and abiotic factors
can be studied in easily in a community or population more easily. Organismal and
ecosystem ecology might be more difficult for collaboration.
d. It is easier to study organismal and ecosystem ecology as the effect of biotic and abiotic factors
can be studied in an organism or ecosystem more easily. Community and population ecology might be more difficult for collaboration.

Check back soon!

Problem 40

How do organisms return nutrients and water to the environment?
a. By cycling between the abiotic and biotic environment.
b. By cycling between evaporation and transpiration.
c. By cycling between the flora and fauna of the Earth.
d. By cycling between temperature and moisture.

April T.

Numerade Educator

Problem 41

Define and give an example of organismal, population and community ecology
a. Organismal ecology includes the study of the number of individuals in an area as well as how
and why population size changes over time, such as a study of the drop in antelope population.
Population ecology includes the study of adaptations that enable individuals to live in specific habitats, such as a study of the use of opposable thumbs. Community ecology includes the study of the processes and consequences of interactions within and among different species
in an area, such as a study of interactions between wolves and deer.
b. Organismal ecology includes the study of the processes and consequences of interactions
within and among different species in an area, such as a study of the interactions between wolves and deer. Population ecology includes the study of the number of individuals in an area as well as how and why population size changes over time, such as a study of the drop in antelope
population. Community ecology includes the study of adaptations that enable individuals to live in specific habitats, such as a study of the use of opposable thumbs.
c. Organismal ecology includes the study of adaptations that enable individuals to live in
specific habitats, such as a study of the use of opposable thumbs. Population ecology includes the study of the number of individuals in an area as well as how and why population size changes over time, such as a study of the drop in antelope population. Community ecology includes studies
of the processes and consequences of interactions within and among different species in an area, such as a study of the interactions between wolves and deer.
d. Organismal ecology includes studies of the adaptations that enable individuals to live in
specific habitats, such as a study of the use of opposable thumbs. Population ecology includes
studies of the processes and consequences of interactions within and among different species
in an area, such as a study of the interactions between wolves and deer. Community ecology includes studies of the number of individuals in an area as well as how and why population size
changes over time, such as a study of the drop in antelope population.

Rikhil M.

Numerade Educator

Problem 42

Many endemic species are found in areas that are geographically isolated. Suggest a plausible scientific explanation why this is so.
a. Geographically isolated areas have provided high temperature conditions for certain species
to evolve. Over time, these species retained their unique characteristics because they remained
separated from other species.
b. Geographically isolated areas have provided a unique environment for certain species to
evolve. Over time, these species retained their unique characteristics because they remained
separated from other species.
c. Certain species are introduced into some geographically isolated areas, which provide them unique environments. Over time, these species retained their unique characteristics because they remained separated from other species.
d. A unique environment is provided for certain species to evolve in vitro and these species are
introduced into geographically isolated areas. Over time, these species retained their unique
characteristics because they remained separated from other species.

April T.

Numerade Educator

Problem 43

The American white pelican migrates from North America to Central America in the winter months. Give three reasons why these birds follow an annual migration pattern.
a. The American white pelican follows an annual migration pattern in search of suitable mates,
warmer climates, and suitable habitat. Warmer climates help them in maintaining a constant body temperature.
b. The American white pelican follows an annual migration pattern in search of food, salt water,
and cooler climates. Cooler climates help these birds in reproduction.
c. The American white pelican follows an annual migration pattern in search of food, warmer
climates, and suitable habitat. Warmer climates help them in maintaining a constant body temperature.
d. The American white pelican follows an annual migration pattern in search of warmer climates
only. Warmer climates help them in maintaining a constant body temperature.

Rikhil M.

Numerade Educator

Problem 44

Why is it essential for organisms to maintain a constant body temperature? Describe adaptations that help the organisms cope with changes in environmental temperature.
a. The rate of metabolic processes increases at very high or low temperatures. So, organisms have to maintain a constant body temperature. This can be achieved only by migration to avoid seasonal
temperature changes.
b. Enzymes that carry out metabolic processes are denatured at very high temperatures. So, organisms have to maintain a constant body temperature. This can be achieved by hibernation, aestivation, or migration.
c. The rate of metabolic processes increases at very high or low temperatures. So, organisms have to maintain a constant body temperature. This can be achieved by hibernation, aestivation, or
migration.
d. Enzymes that carry out metabolic processes are denatured at very high temperatures. So,
organisms have to maintain a constant body temperature. This can be achieved only by migration to avoid seasonal temperature changes.

April T.

Numerade Educator

Problem 45

The extremely low precipitation of subtropical desert biomes might lead one to expect fire to be a major disturbance factor. However, fire is more common in the temperate grassland biome than in the sub tropic desert biome. Why is this?
a. Due to higher net primary productivity, biomass in deserts is significantly more than in temperate
grassland biomes. However, it is easier for fire to spread in grasslands as they are found in abundance.
b. Due to lower net primary productivity, biomass in deserts is significantly less than in temperate
grassland biomes. It is easier for fire to spread in grasslands as they are found in abundance.
c. Due to lower net primary productivity, biomass in deserts is significantly less than in temperate grassland biomes. It is easier for fire to spread in grasslands as they have very low precipitation and high temperatures.
d. Due to higher net primary productivity, biomass in deserts is significantly more than in temperate
grassland biomes. However, it is easier for fire to spread in grasslands as they have very low precipitation and high temperatures.

Rikhil M.

Numerade Educator

Problem 46

What are endemic species? Give an example and explain how endemic species differ from generalist
species.
a. Endemic species are found naturally in specific geographic areas that are usually restricted in
size. For example, the raccoon is found only in Australia. Generalist species are found in a wide
range of geographical locations. For example, the koala is native to most of North and Central
America.
b. Endemic species are those which are likely to be extinct. For example, the koala (a marsupial) is
found only in Australia. Generalist species are found in a wide range of geographical locations.
For example, the raccoon is native to most of North and Central America.
c. Endemic species are found in a wide range of geographical locations. For example, the koala
(a marsupial) is found only in Australia. Generalist species are found naturally in specific geographic areas that are usually restricted in size. For example, the raccoon is native to most
of North and Central America.
d. Endemic species are found naturally in specific geographic areas that are usually restricted in
size. For example, the koala (a marsupial) is found only in Australia. Generalist species are found in a wide range of geographical locations. For example, the raccoon is native to most of North and Central America.

April T.

Numerade Educator

Problem 47

Deserts and subtropical deserts experience low precipitation and extremes in temperature. For a plant to survive and reproduce, what adaptations should it have? Why?
a. To survive, they need prop roots, reduced foliage and fleshy leaves with sunken stomata to reduce
transpiration. Also, they should have seeds that can remain dormant over long periods.
b. To survive, they need deep roots, reduced foliage and fleshy leaves with sunken stomata to reduce
transpiration. Also, they should have seeds that can remain dormant over long periods.
c. To survive, they need deep roots, reduced foliage and fleshy leaves with sunken stomata to reduce
transpiration. Also, these plants need to grow in clumps.
d. To survive, they need deep roots, increased foliage, and fleshy leaves with sunken stomata to reduce transpiration. Also, the plants need seeds
that can remain dormant over long periods.

Rikhil M.

Numerade Educator

Problem 48

In what ways are the subtropical desert and the arctic tundra similar?
a. Both are characterized by animals, which are adapted to burrowing.
b. Both are characterized by plants, which prefer to grow in clumps.
c. Both are characterized by low water availability and, as a result, low net primary productivity.
d. Both are characterized by plants, which are mostly perennials

April T.

Numerade Educator

Problem 49

Describe the chaparral biome. How does it does it differ from subtropical deserts?
a. Shrubs dominate chaparral vegetation and are well adapted to the periodic fires in the area.
Ashes left behind after fires are rich in nutrients, which promote regrowth. Subtropical deserts are
characterized by their high precipitation and water-retaining plants.
b. Shrubs dominate chaparral vegetation and are well adapted to the periodic fires in the area. Ashes left behind after fires are rich in nutrients, which promote regrowth. Subtropical deserts are
characterized by their low precipitation and water-retaining plants.
c. Lichens dominate chaparral vegetation and are well adapted to the periodic fires in the area.
Ashes left behind after fires are rich in nutrients, which promote regrowth. Subtropical deserts are characterized by their low precipitation and water-retaining plants.
d. Shrubs dominate chaparral vegetation but are not well adapted to the periodic fires in the area. Ashes left behind after fires are rich in nutrients, which promote regrowth. Subtropical deserts are
characterized by their low precipitation and water-retaining plants.

Rikhil M.

Numerade Educator

Problem 50

What happens to aquatic life in deep lakes when water freezes during the winter months?
a. During winters, layer of ice falls on water surface as it is less dense than water. Water is densest at $7^{\circ} \mathrm{C}$ and retains its liquid form below the water surface. The aquatic life can exist in
liquid water.
b. During winters, the aquatic life exists in liquid water, which is present below the surface layer, by consuming more resources so they can survive during the harsh winter season.
c. During winters, a layer of ice forms on the water surface, as ice is less dense than water. Water is densest at $4^{\circ} \mathrm{C}$ and retains its liquid form below the water surface, where the ice layer is. In liquid water, the aquatic life can survive using the resources available.
d. During winters, ice forms only on the surface and a few meters below the surface of water. Water is densest at $4^{\circ} \mathrm{C}$ and retains its liquid form below the water surface, where the ice layer is. In liquid water, the aquatic life can exist using the resources available.

April T.

Numerade Educator

Problem 51

Explain the challenges facing organisms living in the intertidal zone and their adaptations to meet these challenges.
a. They are subject to constant exposure to air, sunlight, periods of dryness, and pounding waves. For this reason, some species have an exoskeleton.
b. They are subject to periodic exposures to air, sunlight, periods of dryness, and pounding waves. For this reason, some species have an exoskeleton.
c. They are subject to periodic exposures to air, sunlight, periods of dryness, and pounding waves. For this reason, all species have an exoskeleton.
d. They are subject to periodic exposures to air, sunlight, periods of dryness, and pounding waves. For this reason, most species have an endoskeleton.

Rikhil M.

Numerade Educator

Problem 52

If algae grows out of proportion as seen during algal blooms, how does it affect the ecosystem?
a. Photosynthetic organisms will not be able to grow. The animals and birds that live on those
organisms will be affected. As the algae die, oxygen will be depleted, affecting fish and other
aquatic animals. The pH of water will change, affecting metabolic processes as well.
b. Non-photosynthetic organisms will not be able to grow due to lack of light. The photosynthetic
organisms that require them to live will be affected. As the algae die, oxygen will be depleted, affecting fish and other aquatic animals. The pH of water will change, affecting metabolic processes as well.
c. Photosynthetic organisms will not be able to grow. The animals and birds that live on those
organisms will be affected. As the algae die, carbon dioxide will be depleted, affecting fish and other aquatic animals. The pH of water will change, affecting metabolic processes as well.
d. Non-photosynthetic organisms will not be able to grow. The animals and birds that live on those
organisms will be affected. As the algae die, carbon dioxide will be depleted, affecting fish and other aquatic animals. The pH of water will change, affecting metabolic processes as well.

April T.

Numerade Educator

Problem 53

What are some abiotic factors that affect freshwater biomes? Explain.
a. Salinity and sunlight are both abiotic factors that influence life in freshwater biomes. As organisms living in freshwater biomes require high salt density for survival, its depletion would
kill the organisms. Many organisms that serve as food for others are photosynthetic and would die
if algae blooms obscured the light. Their decomposition as well as the depletion of oxygen by algae would cause organisms that require oxygen to die out as well.
b. Salinity and sunlight are both abiotic factors that influence life in freshwater biomes. As
organisms living in freshwater biomes cannot tolerate high salt levels, these organisms would
not survive if it increased. Many organisms that serve as food for others are photosynthetic
would die if algal blooms obscured the light. Their decomposition and the depletion of carbon
dioxide by algae would cause organisms that require carbon dioxide to die out as well.
c. Salinity and sunlight are both abiotic factors that influence life in freshwater biomes. As
organisms living in freshwater biomes cannot tolerate high salt levels, these organisms would
not survive if it were to increase significantly. Many organisms that serve as food for others are
photosynthetic and would die if algal blooms obscure light. Their decomposition and depletion
of oxygen by algae would cause organisms that require oxygen to die out as well.
d. Salinity and temperature are both abiotic factors that influence life in freshwater biomes. As
organisms living in freshwater biomes cannot tolerate high salt concentrations, those organisms would not survive if salt concentrations increased significantly. Many organisms that serve as food for others are photosynthetic and would die if algal blooms obscured the light. Their decomposition and the depletion of oxygen by algae would cause organisms that require oxygen to die out as well

Rikhil M.

Numerade Educator

Problem 54

Is it possible to reverse global warming? What measures may help in reducing global climate change?
a. It is possible to reverse global warming by reducing the usage of fossil fuels, using alternative fuels, using alternatives to CFC’s and using natural sources of energy.
b. It is not possible to reverse global warming, as major climate changes have already been occurred and settled in the environment. Reducing fossil fuel usage, using natural sources of energy and alternative fuels may slow down global climate change.
c. It is not possible to reverse global warming, as we are already witnessing changes in the environment, plants and animal behavior. Reducing fossil fuel usage and using natural sources of energy may slow down global climate change.
d. It is possible to reverse global warming by working on new technologies that will help in preventing temperature changes worldwide. Using wind power and high efficiency natural gas generation will help in achieving this goal.

April T.

Numerade Educator

Problem 55

As global temperatures change, many flowering plants are flowering earlier. What change would most likely occur if the insect pollinators are not around at the same time?
a. Insects will be deprived of their nectar, leading to decrease in numbers; but flowering plants will
not be affected, as other animals will pollinate them.
b. Flowering plants will not be pollinated resulting in their less population; but insects will not be
affected, as insects will feed on other organisms.
c. Neither plants nor pollinators will be affected, as new or different species of insects are going to
pollinate the flowering plants.
d. Both plant and pollinator numbers would decrease, as insects will be deprived of nectar and plants will not be pollinated.

Rikhil M.

Numerade Educator

Problem 56

If scientists had to predict the rise in Earth’s temperature in the next one hundred years, what would
they take into consideration?
a. Scientists can predict the change in earth’s temperature only by analyzing previous and current data such as dimensions and locations of glaciers as well as the water levels in lakes,
rivers, and oceans.
b. Scientists could predict rise in temperature by analyzing previous and current data like dimensions and locations of glaciers, water levels in lakes, rivers and oceans and by counting and examining number of annual rings in trees.
c. Scientists could predict rise in earth’s temperature by measuring the greenhouse gases present in the current atmosphere. Counting and examining the number of annual rings in trees would also point to the climactic changes over the years.
d. Scientists can predict the change in earth’s atmosphere by counting and analyzing the number of annual rings in trees. Also, analyzing ice cores for over a year would predict the rise in Earth’s temperature in the next one hundred years.

April T.

Numerade Educator

Problem 57

Many people cannot imagine a world without fossil fuels, but fossil fuels are finite resources and will
eventually run out. This is why drilling had begun in Arctic in an effort to find a new source of fossil fuels, though it is currently stopped. What are the dangers of drilling in the Arctic? What are the alternatives?
a. Drilling as well as melting of ice in the Arctic results in the release of large amounts of methane, accelerating global warming. Investing in clean energy like wind, water, and solar power, which do not release harmful gases, could be the alternative.
b. Drilling as well as melting of ice in the Arctic results in the release of large amounts of carbon
monoxide, accelerating global warming. Investing in clean energy like wind, water, and solar power, which do not release harmful gases, could be the alternative.
c. Drilling as well as melting of ice in the Arctic results in the release of large amounts of carbon
monoxide, which is lethal and can cause death. Investing in clean energy like wind, water, and solar power, which do not release harmful gases, could be the alternative.
d. Drilling as well as melting of ice in the Arctic results in the release of large amounts of methane, accelerating global warming. Investing in mining of earth minerals and metal ores could be the alternative.

Rikhil M.

Numerade Educator

Problem 58

The Karner blue butterfly has been declared an endangered species. It is dependent on wild lupine for larval development. The butterfly species, which was found abundantly in Indiana Dunes National Park, is now found further North in Wisconsin and Michigan. Wild lupine has been destroyed in areas where it grew abundantly because of development and construction in the open grasslands where it prefers to grow. Which of the following biotic factors are present in the community?
a. Karner blue butterfly
b. Karner blue butterfly and wild lupine
c. Karner blue butterfly, wild lupine, and fire
d. Karner blue butterfly, wild lupine, and grasslands

April T.

Numerade Educator

Problem 59

In a temperate grassland system area of North America, vegetation has been destroyed by fire. What will happen to the net primary productivity and the local ecosystem when rains return in the next season?
a. The grasses will grow back, but the herbivores that lived there will not return, as they would
have found new land to live on. Therefore, the net primary productivity would decrease.
b. The grasses will not grow back, therefore the herbivores that lived there will not return. Thus,
the net primary productivity would decrease.
c. The grasses will grow back and the herbivores that lived there will return. The net primary
productivity should also be similar to the previous season.
d. The grasses will grow back and the herbivores that lived there will return. The net primary
productivity would be less than the previous season.

Rikhil M.

Numerade Educator

Problem 60

The Karner blue butterfly larva secretes a carbohydrate, which is a source of energy for ants. In turn,
ants tend to the larva, increasing its likelihood to grow into an adult butterfly. This is an example of _____. a. predation
b. competition
c. mutualism
d. parasitism

April T.

Numerade Educator

Problem 61

A lake in the Midwest witnesses a sudden increase in the algae population (algae bloom) that covers the lake. The factors that affect net primary productivity are __.
a. Light and nutrient availability
b. predation by primary consumers
c. pollution
d. carbon d oxide

Rikhil M.

Numerade Educator

Problem 62

Paleontologists have discovered bodies of humans and animals in bogs that have been there for hundreds of years in a perfectly preserved state. Explain the reason for this.
a. Bogs have high oxygen content and organic acids, which lowers the pH. Low pH and high oxygen content prevents oxidation thus, slowing down decomposition.
b. Bogs have low oxygen content and organic acids, which increases the pH. High pH and low oxygen content prevents oxidation thus, slowing down decomposition.
c. Bogs have low oxygen content and organic acids, which lowers the pH. Low pH and low oxygen content prevent oxidation, thus slowing down decomposition.
d. Bogs have low oxygen content and organic acids, which lowers the pH. Low pH and low oxygen content prevents reduction, thus slowing down decomposition.

April T.

Numerade Educator

Problem 63

You are asked to estimate the nutrient content of a lake and its possible effect on net primary productivity. What data will you collect to determine the effect?
a. Sample water from different parts of the lake and determine nutrient composition
b. Sample the carbon content of the phytoplankton growing
c. Take sample of lake water and artificially enrich it, then see the effect of the enrichment on phytoplankton growth compared with growth in unenriched lake water
d. Wait for spring turnover to check for nutrients found in the ocean floor

Rikhil M.

Numerade Educator

Problem 64

The population of a certain species of deer has been reduced drastically because of indiscriminate hunting. How will you determine its impact on the local ecosystem?
a. To determine the effect of indiscriminate hunting on local ecosystem, environmental conditions
should be determined. If a drastic change in environmental conditions is observed then, indiscriminate hunting of deer should be discouraged.
b. The number of predators, their effect on plants they feed on, availability of nutrients in soil, and
number of pests should be determined. If there is a drastic change in numbers, then indiscriminate hunting of deer should be discouraged.
c. Determining the number of predators alone is sufficient to determine the impact of
indiscriminate hunting on local ecosystem. If there is a drastic change in numbers, then
indiscriminate hunting of deer should be discouraged.
d. Determination of the availability of nutrients in soil helps in determining the impact of indiscriminate hunting on local ecosystem. If there is a drastic change in the availability, then
indiscriminate hunting of deer should be discouraged.

April T.

Numerade Educator

Problem 65

In a forest fire, many oak trees were destroyed. After the fire, numerous taller trees replaced the oak trees. What is the best explanation of this event?
a. The tall trees grow faster and create a canopy, which did not allow oak trees to grow.
b. The burning of the trees changed the pH of the soil, which did not allow oak to grow.
c. Roots of shrubs and trees proliferate, taking over the place of the oak trees.
d. Oak trees succumb to pests, thus other pest resistant trees are able to proliferate.

Rikhil M.

Numerade Educator

Problem 66

What are possible consequences if there is a big oil spill in the middle of the ocean? How will it affect the
biodiversity and the net primary productivity? What are some strategies to clean up this oil spill?
a. Oil spills increase the amount of light and oxygen entering the ocean. The phytoplanktons
may perish. Presence of oil would limit mobility of marine animals and may result in death. Some
chemicals and bioremediation can help oil clean up.
b. Oil spills increase the amount of light and oxygen entering the ocean. The phytoplanktons may increase. The mobility of marine animals increases. Biodiversity and, therefore, net primary productivity increases. Some chemicals and bioremediation can help oil clean up.
c. Oil spills cover the surface of the ocean, reducing the amount of light entering the ocean. The marine organisms that can survive independent of light will not be affected. Some
chemicals and bioremediation can help oil clean up.
d. Oil spills cover the surface of the ocean, reducing the amount of light and oxygen entering the ocean. The phytoplankton may perish. Presence of oil would limit mobility of marine animals and may result in death. Some chemicals and bioremediation can help oil clean up

April T.

Numerade Educator

Problem 67

Global climate change has led to butterflies emerging earlier and amphibians mating earlier in the United Kingdom. What impact is it most likely to have on their populations in the next few years?
a. There will be no impact on butterfly and amphibian population.
b. Their numbers will definitely decline with rising temperatures.
c. Their numbers will decline as their plant hosts of butterflies may not flower earlier and young
amphibians may not be viable as there might be a lack of water.
d. It is hard to predict what will happen to their populations as there are no similar studies.

Rikhil M.

Numerade Educator

Problem 68

What are possible short-term and long-term effects of natural and human-induced processes on global climate change and, consequently, ecosystems?
a. Short term changes include melting of glaciers, rise in levels of water bodies which may cover
islands close to sea level, destroying the local ecosystem and animals, and so on. Long-term
changes experienced could include changes in seasonal patterns, unseasonal rainfall, and changes in the life cycle of insects.
b. Short term changes include changes in seasonal patterns, unseasonal rainfall, changes in the life
cycle of insects and animals, and so on. Longterm changes could be change in flowering times
of flowers, and the rise in levels of water bodies, which may cover islands close to sea level, destroying the local ecosystem.
c. Short-term changes include changes in seasonal patterns,unseasonal rainfall, changes in the life
cycle of insects and animals, and so on. Longterm changes could be melting of glaciers, and a
rise in levels of water bodies which may cover islands close to sea level, destroying the local ecosystem.
d. Short term changes include melting of glaciers, unseasonal rainfall, changes in the life cycle of
insects and animals, etc. Long-term changes could be rise in levels of water bodies which may cover islands close to sea level, destroying the local ecosystem.

April T.

Numerade Educator

Problem 69

Twenty targets for the protection of biodiversity by 2020 were established by the 2010 Convention on Biological Diversity. Midway to the target date it is widely agreed that the goals will not be met. The 2016 Living Planet Report from the World Wildlife Federation claims global populations of animals fell by 58 percent between 1970 and 2012 and extrapolates the loss by 2020 to 67%. E.O. Wilson's estimate of the current extinction rate is three species per hour. Geologic periods are defined by mass extinctions. The proposed name for the current geological period is the Anthropocene (Waters et al., Science, 2016). During the current period of mass extinction, human activities are driving loss of habitat and climate change. Climate change during the last 500,000 years is a direct consequence of rising atmospheric $\mathrm{CO}_{2}$ levels, as the Graph shows. The relative abundance of $\mathrm{O}^{16}$ and $\mathrm{O}^{18}$ isotopes can be used to infer temperature because as temperature increases the lower mass isotope is enriched in the atmosphere (objects with a smaller mass have a higher velocity at equal molecular kinetic energy that is proportional to temperature).
Figure 35.31
The role of humans in the last great extinction, the Holocene Extinction, during which the megafauna such as the wooly mammoth, the wooly rhinoceros and the giant deer disappeared, has long been debated. Did we hunt these creatures to extinction? By examining all available DNA evidence, Cooper et al. (Science, 349, 2015) have compared time extinction intervals with these oscillations of climate as shown in the table.
Additionally, the data shown in the graph below are obtained from ice cores. The deeper the sample, the older the sample. The percent departure from the current $\mathrm{O}^{18}$ percentage that is graphed above is a measure of temperature relative to the present temperature. The higher the isotope concentration, the higher the average temperature of the ocean
A. Refine the graph by adding the interval of time of extinction with a label drawn from the table as shown by “a”.
B. Analyze these data in terms of the clustering of extinction events.
C. Based on your analysis, explain how ecosystems have changed during the last 40,000 years, changed and identify the factor that caused these changes.
D. Based on the correlation between Earth’s temperature and the concentration of $\mathrm{CO}_{2}$ in the atmosphere, predict what will happen to animal populations in the future.

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