Question 1

What is the limiting factor for the growth of trees in the tundra?

Accepted Answer

A)  low precipitation 
B)  lack of sunlight 
C)  insufficient minerals in bedrock 
D)  pH of soils 
E)  permafrost 
A)  low precipitation 
B)  lack of sunlight 
C)  insufficient minerals in bedrock 
D)  pH of soils 
E)  permafrost

Question 2

Which statement best explains survivorship curve B?

Accepted Answer

A)  It is likely a species that provides little postnatal care, but lots of care for offspring during midlife, as indicated by increased survivorship. 
B)  This curve is likely of a species that produces lots of offspring, only a few of which are expected to survive. 
C)  It is likely a species where no individuals in the cohort die when they are at 60-70% relative age. 
D)  There was a mass emigration of young to middle-aged individuals in this cohort. 
E)  Survivorship can only decrease; therefore, this curve could not happen in nature. 
A)  It is likely a species that provides little postnatal care, but lots of care for offspring during midlife, as indicated by increased survivorship. 
B)  This curve is likely of a species that produces lots of offspring, only a few of which are expected to survive. 
C)  It is likely a species where no individuals in the cohort die when they are at 60-70% relative age. 
D)  There was a mass emigration of young to middle-aged individuals in this cohort. 
E)  Survivorship can only decrease; therefore, this curve could not happen in nature.

Question 3

Exponential growth of a population is represented by dN/dt =

Accepted Answer

A)    . 
B)  rN. 
C)  rN (K + N). 
D)  rN   . 
E)  rN   . 
A)    . 
B)  rN. 
C)  rN (K + N). 
D)  rN   . 
E)  rN   .

Question 4

Trees are rare in the savanna biome because of

Accepted Answer

A)  insufficient annual precipitation. 
B)  acidic soils. 
C)  frequent fires. 
D)  large variations in seasonal rainfall. 
E)  permafrost. 
A)  insufficient annual precipitation. 
B)  acidic soils. 
C)  frequent fires. 
D)  large variations in seasonal rainfall. 
E)  permafrost.

Question 5

Why is the climate drier on the leeward side of mountain ranges that are subjected to prevailing winds?

Accepted Answer

A)  Deserts create dry conditions on the leeward side of mountain ranges. 
B)  The sun illuminates the leeward side of mountain ranges at a more direct angle, creating heat energy that evaporates most of the water present. 
C)  Pushed by the prevailing winds on the windward side, air is forced to rise, cool, condense, and drop its precipitation, leaving drier air to descend the leeward side. 
D)  Air masses pushed by the prevailing winds are stopped by mountain ranges, and the moisture is used up in the stagnant air masses on the leeward side. 
E)  When compared to the windward side, more organisms live on the sheltered, leeward side of mountain ranges where their utilization of water lowers the amount available. 
A)  Deserts create dry conditions on the leeward side of mountain ranges. 
B)  The sun illuminates the leeward side of mountain ranges at a more direct angle, creating heat energy that evaporates most of the water present. 
C)  Pushed by the prevailing winds on the windward side, air is forced to rise, cool, condense, and drop its precipitation, leaving drier air to descend the leeward side. 
D)  Air masses pushed by the prevailing winds are stopped by mountain ranges, and the moisture is used up in the stagnant air masses on the leeward side. 
E)  When compared to the windward side, more organisms live on the sheltered, leeward side of mountain ranges where their utilization of water lowers the amount available.

Question 6

Which of the following is most likely to contribute to density-dependent regulation of populations?

Accepted Answer

A)  the conversion of ethanol to carbohydrates by yeasts 
B)  intraspecific competition for nutrients 
C)  earthquakes 
D)  floods 
E)  fires 
A)  the conversion of ethanol to carbohydrates by yeasts 
B)  intraspecific competition for nutrients 
C)  earthquakes 
D)  floods 
E)  fires

Question 7

Deserts typically occur in a band around 30 degrees north and 30 degrees south latitude because

Accepted Answer

A)  descending air masses originating from the tropics tend to be dry. 
B)  trade winds have little moisture. 
C)  moisture-laden air is heavier than dry air and is not carried to these latitudes. 
D)  these locations get the most intense solar radiation of any location on Earth. 
A)  descending air masses originating from the tropics tend to be dry. 
B)  trade winds have little moisture. 
C)  moisture-laden air is heavier than dry air and is not carried to these latitudes. 
D)  these locations get the most intense solar radiation of any location on Earth.

Question 8

Which of the following methods would most accurately measure the density of the population being studied?

Accepted Answer

A)  counting the number of prairie dog burrows per hectare 
B)  counting the number of times a 1-km transect is intersected by tracks of red squirrels after a snowfall 
C)  counting the number of coyote droppings per hectare 
D)  counting the number of moss plants in 1-m2 quadrats 
E)  counting the number of zebras from airplane observations. 
A)  counting the number of prairie dog burrows per hectare 
B)  counting the number of times a 1-km transect is intersected by tracks of red squirrels after a snowfall 
C)  counting the number of coyote droppings per hectare 
D)  counting the number of moss plants in 1-m2 quadrats 
E)  counting the number of zebras from airplane observations.

Question 9

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.

Accepted Answer

A)  120 individuals added 
B)  40 individuals added 
C)  20 individuals added 
D)  400 individuals added 
E)  20 individuals lost 
A)  120 individuals added 
B)  40 individuals added 
C)  20 individuals added 
D)  400 individuals added 
E)  20 individuals lost

Question 10

Please use the following information to answer the question(s) below.
In areas of permafrost, stands of black spruce are frequently observed in the landscape, whereas other tree species are noticeably absent. Often these stands are referred to as "drunken forests" because many of the black spruce are displaced from their normal vertical alignment.
-When climbing a mountain, we can observe transitions in biological communities that are analogous to the changes

Accepted Answer

A)  in different depths in the ocean. 
B)  in biomes at different latitudes. 
C)  in a community through different seasons. 
D)  in an ecosystem as it evolves over time. 
A)  in different depths in the ocean. 
B)  in biomes at different latitudes. 
C)  in a community through different seasons. 
D)  in an ecosystem as it evolves over time.

Question 11

Why do some invertebrates, such as lobsters, show a "stair-step" survivorship curve?

Accepted Answer

A)  Many invertebrates mate and produce offspring on multiyear cycles. 
B)  Within a species of invertebrates, younger individuals have a higher survivorship than older individuals. 
C)  Many invertebrates molt in order to grow, and they are vulnerable to predation during their "soft shell" stage. 
D)  Many invertebrate species have population cycles that go up and down according to the frequency of sunspots. 
E)  The number of fertilized eggs that mature to become females in many species of invertebrates is based on ambient temperature. 
A)  Many invertebrates mate and produce offspring on multiyear cycles. 
B)  Within a species of invertebrates, younger individuals have a higher survivorship than older individuals. 
C)  Many invertebrates molt in order to grow, and they are vulnerable to predation during their "soft shell" stage. 
D)  Many invertebrate species have population cycles that go up and down according to the frequency of sunspots. 
E)  The number of fertilized eggs that mature to become females in many species of invertebrates is based on ambient temperature.

Question 12

Which of the following is a physical factor that can limit the geographic distribution of species?

Accepted Answer

A)  predation 
B)  disease 
C)  soil structure 
D)  nutrients 
E)  pH 
A)  predation 
B)  disease 
C)  soil structure 
D)  nutrients 
E)  pH

Question 13

Palm trees and subtropical plants are commonplace in Land's End, England, whose latitude is the equivalent of Labrador in coastal Canada, where the local flora is subarctic. Which statement best explains why this apparent anomaly exists between North America and Europe?

Accepted Answer

A)  Labrador does not get enough rainfall to support the subtropical flora found in Land's End. 
B)  Regions such as Labrador are actually colder than England because colder Arctic water flows down to eastern North America and warm water from the equator flows to England. 
C)  Rainfall fluctuates greatly in England; rainfall is consistently high in Labrador. 
D)  Labrador is too windy to support tall plants, such as palm trees. 
E)  Labrador receives sunlight of lower duration and intensity than does Land's End. 
A)  Labrador does not get enough rainfall to support the subtropical flora found in Land's End. 
B)  Regions such as Labrador are actually colder than England because colder Arctic water flows down to eastern North America and warm water from the equator flows to England. 
C)  Rainfall fluctuates greatly in England; rainfall is consistently high in Labrador. 
D)  Labrador is too windy to support tall plants, such as palm trees. 
E)  Labrador receives sunlight of lower duration and intensity than does Land's End.

Question 14

In 2008, the New Zealand population was approximately 4,275,000. If the birth rate was 14 births for every 1,000 people, approximately how many births occurred in New Zealand in 2008?

Accepted Answer

A)  6,000 
B)  42,275 
C)  60,000 
D)  140,000 
E)  600,000 
A)  6,000 
B)  42,275 
C)  60,000 
D)  140,000 
E)  600,000

Question 15

Which of the following equations represents zero population growth?

Accepted Answer

A)  b = m or r = 0 
B)  dN/dt = rN 
C)  dN/dt = rN (K - N)/K 
D)  dN/dt = K 
E)  dN/dt = 1.0N 
A)  b = m or r = 0 
B)  dN/dt = rN 
C)  dN/dt = rN (K - N)/K 
D)  dN/dt = K 
E)  dN/dt = 1.0N

Question 16

Figure 40.3
-In Figure 40.3, which curve best describes survivorship in marine molluscs?

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
E)  E 
A)  A 
B)  B 
C)  C 
D)  D 
E)  E

Question 17

The main reason that polar regions are cooler than the equator is that

Accepted Answer

A)  there is more ice at polar regions. 
B)  sunlight strikes polar regions at a lower angle. 
C)  the polar regions are farther from the sun. 
D)  the polar regions' atmosphere is thinner and contains fewer greenhouse gases. 
E)  the polar regions are permanently tilted away from the sun. 
A)  there is more ice at polar regions. 
B)  sunlight strikes polar regions at a lower angle. 
C)  the polar regions are farther from the sun. 
D)  the polar regions' atmosphere is thinner and contains fewer greenhouse gases. 
E)  the polar regions are permanently tilted away from the sun.

Question 18

Which of the following describes a Type II survivorship curve?

Accepted Answer

A)  flat at the start, reflecting low death rates during early and middle life, then dropping steeply as death rates increase among older age groups 
B)  dropping sharply at the start, reflecting very high death rates for the young, then flattening out as death rates decline for those few that survive 
C)  a constant death rate over the organism's life span 
D)  flat at the start, reflecting low death rates during early and middle life, then rising steeply as death rates decrease among older age groups 
A)  flat at the start, reflecting low death rates during early and middle life, then dropping steeply as death rates increase among older age groups 
B)  dropping sharply at the start, reflecting very high death rates for the young, then flattening out as death rates decline for those few that survive 
C)  a constant death rate over the organism's life span 
D)  flat at the start, reflecting low death rates during early and middle life, then rising steeply as death rates decrease among older age groups

Question 19

A population is correctly defined as having which of the following characteristics?
I. inhabits the same general area
II. belongs to the same species
III. possesses a constant and uniform density and dispersion

Accepted Answer

A)  I only 
B)  III only 
C)  I and II only 
D)  II and III only 
E)  I, II, and III 
A)  I only 
B)  III only 
C)  I and II only 
D)  II and III only 
E)  I, II, and III

Question 20

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

Accepted Answer

A)  old growth, because the stable conditions would favor exponential growth of all species in the forest 
B)  old growth, because each of the species is well established and can produce many offspring 
C)  logged, because the disturbed forest affords more resources for increased specific populations to grow 
D)  equally probable in old-growth and logged forests, because disturbed and stable habitats have equal opportunity for tree seedlings to survive 
A)  old growth, because the stable conditions would favor exponential growth of all species in the forest 
B)  old growth, because each of the species is well established and can produce many offspring 
C)  logged, because the disturbed forest affords more resources for increased specific populations to grow 
D)  equally probable in old-growth and logged forests, because disturbed and stable habitats have equal opportunity for tree seedlings to survive

Exam 40: Population Ecology and the Distribution of Organisms

What is the limiting factor for the growth of trees in the tundra?

Which statement best explains survivorship curve B?

Exponential growth of a population is represented by dN/dt =

Trees are rare in the savanna biome because of

Why is the climate drier on the leeward side of mountain ranges that are subjected to prevailing winds?

Which of the following is most likely to contribute to density-dependent regulation of populations?

Deserts typically occur in a band around 30 degrees north and 30 degrees south latitude because

Which of the following methods would most accurately measure the density of the population being studied?

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.

Why do some invertebrates, such as lobsters, show a "stair-step" survivorship curve?

Which of the following is a physical factor that can limit the geographic distribution of species?

Palm trees and subtropical plants are commonplace in Land's End, England, whose latitude is the equivalent of Labrador in coastal Canada, where the local flora is subarctic. Which statement best explains why this apparent anomaly exists between North America and Europe?

In 2008, the New Zealand population was approximately 4,275,000. If the birth rate was 14 births for every 1,000 people, approximately how many births occurred in New Zealand in 2008?

Which of the following equations represents zero population growth?

Figure 40.3 -In Figure 40.3, which curve best describes survivorship in marine molluscs?

The main reason that polar regions are cooler than the equator is that

Which of the following describes a Type II survivorship curve?

A population is correctly defined as having which of the following characteristics? I. inhabits the same general area II. belongs to the same species III. possesses a constant and uniform density and dispersion

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

Introduction: Evolution and the Foundations of Biology

The Chemical Context of Life

Carbon and the Molecular Diversity of Life

A Tour of the Cell

Membrane Transport and Cell Signaling

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

Gene Expression: From Gene to Protein

Regulation of Gene Expression

Development, Stem Cells, and Cancer

Viruses

Genomes and Their Evolution

Descent With Modification

Phylogeny

The Evolution of Populations

The Origin of Species

Broad Patterns of Evolution

Early Life and the Diversification of Prokaryotes

The Origin and Diversification of Eukaryotes

The Colonization of Land by Plants and Fungi

The Rise of Animal Diversity

Plant Structure and Growth

Resource Acquisition, Nutrition, and Transport in Vascular Plants

Reproduction and Domestication of Flowering Plants

Plant Responses to Internal and External Signals

Homeostasis and Endocrine Signaling

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Reproduction and Development

Neurons, Synapses, and Signaling

Nervous and Sensory Systems

Motor Mechanisms and Behavior

Species Interactions

Ecosystems and Energy

Global Ecology and Conservation Biology

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