unit 2 AP human geo unit 2 (S1) [population]

Population

The number of people living in a defined area.

Aging Population

A population with a rising average age and a growing percentage of elderly citizens.

Agricultural Density

The number of farmers per unit of arable (farmable) land.

Arithmetic Density

The total number of people divided by the total land area.

Anti-natalist Policy

A government policy designed to reduce birth rates and slow population growth.

Carrying Capacity

The maximum population size that an environment can sustain without degrading resources.

Census

An official count or survey of a population, recording details such as age, sex, and occupation.

Crude Birth Rate (CBR)

The total number of live births per 1,000 people in a given year.

Crude Death Rate (CDR)

The total number of deaths per 1,000 people in a given year.

Demography

The scientific study of population characteristics such as size, structure, and distribution.

Demographic Momentum

The tendency for population growth to continue despite declining fertility rates due to a large youth population.

Demographic Transition Model (DTM)

A model that shows how birth rates, death rates, and population growth change as countries develop economically.

Dependency Ratio

The ratio of people who are too young or too old to work compared to those in the working-age group.

Developed Country (MDC)

A country with high levels of income, industrialization, and standard of living.

Developing Country (LDC)

A country with low industrial production, income, and standard of living.

Ecumene

The portion of Earth’s surface occupied by permanent human settlement.

Elderly Support Ratio

The number of working-age people (ages 15–64) compared to those aged 65 and older.

Epidemic

A regional outbreak of a disease that affects many people in a community or area.

Epidemiology

The branch of medical science concerned with the incidence, distribution, and control of diseases.

Epidemiologic Transition Model (ETM)

A model explaining how causes of death and disease change with levels of economic development.

Fertility

The average number of children a woman is expected to have during her lifetime.

Industrial Revolution

A period of major industrialization during the 18th–19th centuries that led to population growth and urbanization.

Infant Mortality Rate (IMR)

The number of infant deaths (under age 1) per 1,000 live births.

Life Expectancy

The average number of years a person can expect to live in a given population.

Malthusian Theory

The idea proposed by Thomas Malthus that population growth will outpace food supply, leading to crisis unless controlled.

Mortality

The number of deaths in a population; death rate.

Medical Revolution

The spread of modern medicine that lowered death rates and increased life expectancy, especially in developing countries.

Natural Increase Rate (NIR)

The percentage by which a population grows in a year (CBR – CDR).

Overpopulation

When the number of people exceeds the environment’s ability to support them at a decent standard of living.

Pandemic

A disease that occurs over a wide geographic area and affects a very high proportion of the population.

Population Composition

The structure of a population in terms of age, sex, and other characteristics.

Population-Doubling Time

The number of years needed for a population to double in size, assuming a constant rate of growth.

Population Pyramid / Age-Sex Structure

A bar graph that shows the distribution of a population by age and gender.

Physiological Density

The number of people per unit of arable (farmable) land.

Pronatalist Policy

A government policy that encourages higher birth rates.

Sex Ratio

The number of males per 100 females in a population.

Total Fertility Rate (TFR)

The average number of children a woman will have in her lifetime.

Zero Population Growth (ZPG)

A condition in which a population neither grows nor declines because births equal deaths.

John Snow

A physician who mapped cholera cases in London and helped found modern epidemiology.

Thomas Malthus

An English economist who argued that population growth would exceed food production without limits on births.