Unit 3

Question 1

Population growth rate (intrinsic growth rate)

Answer 1

the number of offspring an individual can produce in a given time period, minus the deaths of the individual or its offspring during that same time period

Question 2

Biotic potential

Answer 2

under ideal conditions, with unlimited resources available, every population has a particular maximum potential for growth

Question 3

K-selected species

Answer 3

species with a low intrinsic growth rate that causes the population to increase slowly until it reaches the carrying capacity of the environment

Question 4

Carrying capacity

Answer 4

the limit to the number of individuals that can be supported by an existing habitat or ecosystem and is denoted as K

Question 5

R-selected species

Answer 5

have a high intrinsic growth rate and their populations typically increase rapidly

Question 6

Overshoot

Answer 6

when a population becomes larger than the environment’s carrying capacity

Question 7

Dieback

Answer 7

a rapid decline in a population due to death. also known as die-off

Question 8

K-selected characteristics

Answer 8

long life span, long time to maturity, few reproductive events, few offspring, larger offspring, parental care, slow growth rate, highly competitive, high impact of invasive species

Question 9

R-selected characteristics

Answer 9

short life span, short time to maturity, many reproductive events, many offspring, small offspring, no parental care, fast growth rate, low competition, low impact of invasive species

Question 10

Survivorship curves

Answer 10

graphs that represent the distinct patterns of species survival as a function of age

Question 11

Type 1 survivorship curve

Answer 11

has a pattern of survival over time in which there is high survival throughout most of the life span, but then individuals start to die in large numbers as they approach old age (elephants, whales, humans)

Question 12

Type 2 survivorship curve

Answer 12

pattern of survival over time in which there is a relatively constant decline in survivorship throughout most of the life span (chipmunks, squirrels)

Question 13

Type 3 survivorship curve

Answer 13

has a low survivorship early in life with few individuals reaching adulthood. Those individuals that reach adulthood tend to live for a long time (mosquitoes, fish, frogs)

Question 14

Density-dependent factors

Answer 14

a factor that influences an individual’s probability of survival and reproduction in a manner that depends on the size of the population

Question 15

Density-independent factors

Answer 15

a factor that has the same effect on an individual’s probability of survival and reproduction at any population size

Question 16

Population growth models

Answer 16

mathematical equations that can be used to predict population size at any moment in time

Question 17

Fecundity

Answer 17

The ability to produce an abundance of offspring

Question 18

Exponential growth model

Answer 18

a growth model that estimates a population’s future size after a period of time based on the biotic potential and the number of reproducing individuals currently in that population

Question 19

J-shaped curve

Answer 19

the curve of the exponential growth model when graphed

Question 20

Logistic growth model

Answer 20

a growth model that describes a population whose growth is initially exponential, but slows as the population approaches the carrying capacity of the environment

Question 21

S-shaped curve

Answer 21

the shape of the logistic growth model when graphed

Question 22

Limiting resource

Answer 22

a resource that a population can’t live without and that occurs in quantities lower than the population would require to increase in size

Question 23

Demography

Answer 23

Study of human populations and population trends

Question 24

Demographer

Answer 24

Scientist in the field of demography

Question 25

Immigration

Answer 25

The movement of people into a country or region, from another country or region

Question 26

Emigration

Answer 26

The movement of people out of a country or region

Question 27

Crude birth rate

Answer 27

The number of births per 1000 individuals per year

Question 28

Crude death rate

Answer 28

The number of deaths per 1000 individuals per years

Question 29

Net migration rate

Answer 29

The difference between immigration and emigration in a given year per 1000 people in a country

Question 30

Life expectancy

Answer 30

The average number of years that an infant born in a particular year in a particular country can be expected to live, given the current average life span and death rate of that country

Question 31

Infant mortality

Answer 31

The number of deaths of children under 1 year of age per 1000 live births

Question 32

Child mortality

Answer 32

The number of deaths of children under age 5 per 1000 live births

Question 33

Environmental justice

Answer 33

The study of the disproportionate exposure to environmental hazards experienced by people of color, recent immigrants, and people of lower socio-economic backgrounds; and is both an academic field and a social movement

Question 34

Age structure diagram

Answer 34

A visual representation of the number of individuals within specific age groups for a country typically expressed for males and females

Question 35

Population pyramid

Answer 35

An age structure diagram that is widest at the bottom and narrowest at the top, typical of developing countries

Question 36

Developing countries

Answer 36

Countries with relatively low levels of industrialization and income

Question 37

Developed countries

Answer 37

Countries that have relatively high levels of industrialization and income

Question 38

Population momentum

Answer 38

Continued population growth after growth reduction measures have been implemented

Question 39

Total fertility rate

Answer 39

An estimate of the average number of children that each woman in a population will bear throughout her childbearing years

Question 40

Family planning

Answer 40

The regulation of the number of spacing of offspring through the use of birth control

Question 41

Replacement-level fertility

Answer 41

The total fertility rate required to offset the average number of deaths in a population in order to maintain the current population size

Question 42

Doubling time

Answer 42

The number of years it takes a population to double

Question 43

Rule of 70

Answer 43

A method which dictates that by dividing the number 70 by the percentage population growth rate we can determine a population's doubling time