Chapter 52

Question 1

The specific environment in which a population lives as a characterized by its biotic and abiotic features

Answer 1

habitat

Question 2

The number of individuals in a population at a specified time

Answer 2

population size

Question 3

The number of individuals per unit area or per unit volume of habitat

Answer 3

population density

Question 4

The spatial distribution of individuals within a population’s geographical range

Answer 4

dispersion

Question 5

a pattern of distribution in which the individuals in a population are distributed unpredictably in their habitat

Answer 5

random dispersion

Question 6

A pattern of distribution in which individuals in a population are grouped together

Answer 6

clumped dispersion

Question 7

A pattern of distribution in which the individuals in a population are evenly spaced in their habitat

Answer 7

uniform dispersion

Question 8

A statistical description or graph of the relative numbers of individuals in each age class in a population

Answer 8

age structure

Question 9

The average time between the birth of an organism and the birth of its offspring

Answer 9

generation time

Question 10

The relative proportions of males and females in a population

Answer 10

sex ratio

Question 11

What is the difference between a population’s size and its density?

Answer 11

A population’s size is simply the number of individuals it contains. Its density is the number of individuals per area r volume of habitat occupied

Question 12

What do the 3 patterns of dispersion imply about the relationships between individuals in a population

Answer 12

a clumped pattern of dispersion implies that individuals in the population help each other or that some vital resource in the environment also has a clumped distribution. A uniform pattern of dispersion implies that individuals in the population repel each other. A random pattern of dispersion does not imply either positive or negative interactions among individuals in the population.

Question 13

movement of organisms into a population

Answer 13

immigration

Question 14

The movement of individual out of a population

Answer 14

emigration

Question 15

The statistical study of the process that change a population’s size and density through time

Answer 15

Demography

Question 16

A chart that summarizes the demographic characteristics of a population

Answer 16

life table

Question 17

A group of individuals of similar age

Answer 17

cohort

Question 18

The proportions of individuals alive at the start of an age interval that died during that age interval

Answer 18

age-specific mortality

Question 19

The proportion of individuals alive at the start of an age interval that survived until the start of the next age interval

Answer 19

age-specific survivorship

Question 20

The average number of offspring produced by surviving females of a particular age

Answer 20

age-specific fecundity

Question 21

Graphic display of the rate of survival of individuals over a species’ life span

Answer 21

survivorship curve

Question 22

What statistics are usually included in a life table?

Answer 22

A life table usually summarizes statistics about the age-specific rate, age-specific mortality rates, and age-specific fecundity of a population

Question 23

Which type of survivorship curve is characteristic of humans in industrialized countries?

Answer 23

humans in the industrialized countries exhibit Type I suvivorship curves because they provide lots of care to their offspring, thus reducing infant and childhood mortality to low levels

Question 24

The lifetime pattern of growth, maturation, and reproduction that is characteristic of a population or species

Answer 24

life histories

Question 25

the total amount of energy that an organism can accumulate and use to fuel its activities

Answer 25

energy budget

Question 26

The amount of energy invested in offspring- in the form of the energy stored in eggs or seeds or energy transferred to developing young through a placenta- before they are born

Answer 26

passive parental care

Question 27

Parents' investment of time and energy in caring for offspring after they are born or hatched

Answer 27

active parental care

Question 28

to what 2 broad categories of activities do children devote their energy budget?

Answer 28

Children spend most of their energy on growth and maintenance; they devote energy to reproduction later in life

Question 29

Why do fecundity and the amount of parental care devoted ot each offspring exhibit an inverse relationship?

Answer 29

fecundity and the amount of parental care devoted to each offspring exhibit an inverse relationship because organisms that produce few offspring can devote substantial time and energy to each, whereas those that produce many offspring can devote only minimal time and energy to each

Question 30

model that describes unlimited population growth

Answer 30

exponential model of population growth

Question 31

The difference between the per capita birth rate and the per capita death rate of a population

Answer 31

per capita growth rate

Question 32

A circumstance in which the birth rate of a population equals the death rate

Answer 32

zero population growth

Question 33

The maximum possible per capita population growth rate in a population living under ideal conditions

Answer 33

intrinsic rate of increase

Question 34

The maximum size of a population that an environment can support indefinitely

Answer 34

carrying capacity

Question 35

model of population growth that assumes that a population's per capita growth rate decrease as the population gets larger

Answer 35

logistic model of population growth

Question 36

The dependence of 2 or more individuals in a population on the same limiting resource

Answer 36

intraspecific

Question 37

the delayed response of organisms to changes in environmental conditions

Answer 37

time lag

Question 38

how does the prediction of the exponential model of population growth differ from that of the logistic model?

Answer 38

The model of exponential population growth predicts unlimited population growth through time, generating a J-shaped curve of population size versus time. The logistic model predicts that population growth slow down as the population approaches its carrying capacity, generating an S-shaped curve of population size versus time

Question 39

What is carrying capacity? is it a property of a habitat or of a population?

Answer 39

carrying capacity is the maximum number of individuals in a population that an environment can support. The carrying capacity is thus a property of the environment with reference to a particular population

Question 40

What is time lag?

Answer 40

A time lag is a delay in a population's response to a changing environment. It may cause population's size to oscillate around its carrying capacity

Question 41

description of environmental factors for which the strength of their efect on a population varies with the population's density

Answer 41

density-dependent

Question 42

Description of environmental factors for which the strength of their effect on a population does not vary with the population's density

Answer 42

density-independent

Question 43

a short-lived species adapted to function well in a rapidly changing environment

Answer 43

r-selected species

Question 44

long-lived species that thrive in more stable environments

Answer 44

K-selected species

Question 45

a group of neighboring populations that exchange individuals

Answer 45

metapopulation

Question 46

in metapopulation analyses, a population that is either stable or increasing in size

Answer 46

source population

Question 47

in metapopulations analysis, a population that routinely declines in size after being replenished by immigrants from a source population

Answer 47

sink population

Question 48

How can you tell whether an environmental factor causes denisity-dependent or density-independent effects on a population?

Answer 48

The effects of density-dependent factors gets stronger(that is, they affect a larger percentage of the individuals in the population) as the population's density increase. The effects of density-independent factors do not change(that is, they affect the same percentage of the individuals in a population) as the population's density changes

Question 49

Are the effects of infectious diseases on populations more likely to be density-dependent or density-independent?

Answer 49

The effects of infectious diseases are usually density-dependent because disease-causing pathogens spread more quickly through dense populations of the organisms they infect

Question 50

A graphical depiction of the historical relationship between a country's economic development and its birth and death rates

Answer 50

demographic transition model

Question 51

a program that educates people about ways to produce an optimal family size on an economically feasible schedule

Answer 51

family planning program

Question 52

How have humans sidestepped the controls that regulate populations of other organisms?

Answer 52

humans have sidestepped the controls that regulate the populations of other organisms by expanding their geographical range to include a wide variety of habitats, by increasing the carrying capacity through agricultural production and by decreasing their death rate through the introduction of medical care and improved sanitation

Question 53

how does the age structure of a population influence its future population growth?

Answer 53

the age structure of a population influences its future population growth by determining how many individuals will reach reproductive age in the future. populations with a bottom-heavy age structure will experience a growth spurt when children alive today reach sexual maturity. populations with a more even age structure will not experience a dramatic future increase in population size

Question 54

The overall spatial boundaries within which a population lives

Answer 54

geographical range