Question 1

Communities are composed of all of the:
A) communities of all the different populations that live together within an area.
B) ecosystems within the biosphere.
C) populations of all the different species that live together within an area.
D) various dispersal patterns of the different species within a given area.
E) population's females' combined reproductive capabilities within the same given unit of time.

Accepted Answer

Communities are composed of populations of all the different species that live together within an area.

Question 2

The organisms associated with patches of floating ocean vegetation would be an example of:
A) random dispersion
B) density-independent distribution
C) uniform dispersion
D) density-dependent distribution
E) clumped dispersion

Accepted Answer

Organisms associated with patches of floating ocean vegetation are typically found in groups or clusters, which is characteristic of clumped dispersion.

Question 3

Which of the following organisms would have the highest intrinsic rate of increase?
A) bacteria
B) blue whales
C) red grouse
D) elephants
E) humans

Accepted Answer

Bacteria have the highest intrinsic rate of increase due to their rapid reproduction and short generation times compared to larger organisms like whales, elephants, and humans.

Question 4

Which of the following relationships is incorrectly paired?
A) schooling fish − aggregated distribution
B) nesting seabirds − random dispersion
C) grove of aspen − clumped dispersion
D) flour beetle larvae − random dispersion
E) adult sand pine − uniform dispersion

Accepted Answer

Nesting seabirds typically exhibit a uniform dispersion due to territorial behavior, not random dispersion.

Question 5

____ is the least frequent of the dispersal patterns seen in nature.
A) Random dispersion
B) Aggregated distribution
C) Uniform dispersion
D) Density-dependent distribution
E) Clumped dispersion

Accepted Answer

The answer of ____ is the least frequent of the...

Question 6

What would be the growth rate ( r ) of an island population of 1000 that has 30 births per 100 population, 20 death per 100 population, 5 immigrants per 100 population, and 10 emigrants per 100 population?
A) +5
B) − 50
C) +50
D) − 150
E) +150

Accepted Answer

The growth rate formula is:
r = (births + immigration) - (deaths + emigration)
r = (30/100 + 5/100) - (20/100 + 10/100)
r = 0.15 - 0.3
r = -0.15
Since the growth rate is negative, it means the population is decreasing. To get the absolute value of the growth rate, we take the positive value, which is 0.15. To convert this to a percentage, we multiply by 100, giving a growth rate of 15%. Since the population is decreasing, the growth rate is negative, but the absolute value of the growth rate is positive, so the correct answer is C: +50.

Question 7

Figure 53-1  The graph in the accompanying figure would best be described as:
A) being characteristic of exponential growth.
B) being characteristic of arithmetic growth.
C) an S-shaped curve.
D) a J-shaped curve.
E) being a J-shaped curve characteristic of exponential growth.

Accepted Answer

The answer of Figure 53-1  The graph in the...

Question 8

When r = 0.00001, the population size:
A) will increase.
B) will decrease.
C) is stable.
D) may increase or decrease, depending on K .
E) may increase or decrease, depending on i .

Accepted Answer

When r (the intrinsic rate of natural increase) is greater than 0, it indicates that the population size will increase, regardless of other factors.

Question 9

What term refers to the average rate at which organisms produce offspring?:
A) doubling time
B) natality
C) emigration
D) stasis
E) survivorship

Accepted Answer

Natality refers to the birth rate or the average rate at which organisms produce offspring.

Question 10

Natural selection acts most directly on:
A) populations.
B) communities.
C) ecosystems.
D) the biosphere.
E) K- selected organisms.

Accepted Answer

Natural selection acts directly on populations as it is the individuals within a population that are selected for based on their traits and ability to survive and reproduce. Communities, ecosystems, and the biosphere are all larger scales of organization that may indirectly be affected by natural selection, but it primarily acts on populations. K-selected organisms are a type of life history strategy, not a scale of organization, and may be subject to natural selection like any other organism.

Question 11

At zero population growth:
A) b = d.
B) b > d.
C) b d.
D) r > 0.
E) r > K .

Accepted Answer

At zero population growth, the birth rate (b) is equal to the death rate (d), meaning there is no net increase or decrease in population size. Therefore, the correct option is A, as all other options represent situations where there is either population growth or decline.

Question 12

Biologists in which of the following applied disciplines must understand population ecology?
A) forestry
B) agronomy
C) wildlife management
D) forestry and agronomy
E) forestry, agronomy, and wildlife management

Accepted Answer

Population ecology is crucial in forestry, agronomy, and wildlife management as it helps in understanding species interactions, resource management, and conservation efforts.

Question 13

Figure 53-1  The equation that would best describe the curve in the accompanying figure is:
A) dN / dt = r .
B) dN / dt = N .
C) dN / dt = rN .
D) dN / dt = rN + I − e .
E) dN / dt = rN ( K − N ).

Accepted Answer

The answer of Figure 53-1  The equation that would...

Question 14

Which of the following series correctly represents the hierarchical organization within ecology?
A) ecosystem → population → community → biosphere
B) biosphere → community → population → ecosystem
C) community → population → ecosystem → biosphere
D) population → community → ecosystem → biosphere
E) population → ecosystem → community → biosphere

Accepted Answer

The correct hierarchy in ecology is population → community → ecosystem → biosphere, where populations of species form communities, communities interact within ecosystems, and ecosystems are part of the biosphere.

Question 15

When r = − 0.00057, the population size:
A) will increase.
B) will decrease.
C) is stable.
D) may increase or decrease, depending on K .
E) may increase or decrease, depending on i .

Accepted Answer

When r is negative, it indicates that the population is decreasing. Therefore, the population size will decrease when r = -0.00057.

Question 16

The best definition of population density is the number of individuals:
A) of all species in a given area.
B) of one species in a given area.
C) in a given area at a given time.
D) of all species in a given area at a given time.
E) of one species in a given area at a given time.

Accepted Answer

Population density refers to the number of individuals of a particular species in a specific area at a given time. Therefore, option E, which states "of one species in a given area at a given time," is the best definition of population density. The other options are either too broad or too narrow in scope.

Question 17

Which of the following consists of organisms, all of which share a common gene pool?
A) a community
B) a population
C) a biosphere
D) an ecosystem
E) a landscape

Accepted Answer

A population consists of organisms of the same species that live in the same area and share a common gene pool.

Question 18

Clumped dispersion is often influenced by:
A) the presence of strange groups.
B) sexual reproduction in plants or invertebrates.
C) unlimited seed dispersal in plants.
D) a patchy distribution of resources.
E) homogenous environments.

Accepted Answer

Clumped dispersion occurs when individuals are found in patches within a population. This pattern is often influenced by a patchy distribution of resources, where individuals gather in areas where resources are abundant.

Question 19

Which set of values would result in a population with a growth rate of zero?
A) b = 1000, d = 500, i = 750, e = 1000
B) b = 1000, d = 500, i = 1000, e = 1000
C) b = 1000, d = 500, i = 1500, e = 1000
D) b = 1000, d = 500, i = 0, e = 1000
E) b = 1000, d = 500, i = 500, e = 1000

Accepted Answer

The answer of Which set of values would result in...

Question 20

The logistic equation:
A) models a J-shaped growth curve.
B) takes into account the carrying capacity of the environment.
C) predicts continued exponential growth.
D) characterizes the uncontrolled growth of a population.
E) models a K -shaped growth curve.

Accepted Answer

The logistic equation takes into account the carrying capacity of the environment, which is the maximum population size that the environment can support. As the population approaches this limit, the growth rate slows down and eventually reaches a plateau, resulting in an S-shaped or logistic growth curve.

Quiz 53: Introduction to Ecology Population Ecology

Communities are composed of all of the:

The organisms associated with patches of floating ocean vegetation would be an example of:

Which of the following organisms would have the highest intrinsic rate of increase?

Which of the following relationships is incorrectly paired?

____ is the least frequent of the dispersal patterns seen in nature.

What would be the growth rate ( r ) of an island population of 1000 that has 30 births per 100 population, 20 death per 100 population, 5 immigrants per 100 population, and 10 emigrants per 100 population?

Figure 53-1 The graph in the accompanying figure would best be described as:

When r = 0.00001, the population size:

What term refers to the average rate at which organisms produce offspring?:

Natural selection acts most directly on:

At zero population growth:

Biologists in which of the following applied disciplines must understand population ecology?

Figure 53-1 The equation that would best describe the curve in the accompanying figure is:

Which of the following series correctly represents the hierarchical organization within ecology?

When r = − 0.00057, the population size:

The best definition of population density is the number of individuals:

Which of the following consists of organisms, all of which share a common gene pool?

Clumped dispersion is often influenced by:

Which set of values would result in a population with a growth rate of zero?

The logistic equation: