MCAT Psychological Social Foundations Flashcards: 9b Demographic Transition Pyramids

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This deck focuses on 9b Demographic Transition Pyramids, giving you a quick way to review the definitions, rules, and examples that matter most for MCAT Psychological Social Foundations.

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Flashcard 1: What is the total fertility rate (TFR) definition in demography?

Answer: Average number of children a woman has over her lifetime. TFR estimates long-term population replacement potential, accounting for fertility patterns across reproductive ages.

Flashcard 2: What is a population pyramid?

Answer: An age-by-sex distribution graph for a population. Shows age structure with males left, females right of center.

Flashcard 3: What is the demographic transition model (DTM) used to describe in populations over time?

Answer: A stage model linking development to birth and death rate changes. It outlines the progression of societies from pre-industrial high rates to post-industrial low rates, correlating with economic and social advancements.

Flashcard 4: What defines DTM Stage 3 (late expanding) in terms of birth and death rates?

Answer: Declining birth rate with low death rate; slowing growth. Urbanization and education reduce fertility as mortality stays low.

Flashcard 5: Which population pyramid shape indicates slow growth and low fertility?

Answer: Stationary/rectangular pyramid with similar cohort widths. Equal-width bars show stable births and low mortality.

Flashcard 6: What is the defining pattern of Stage 5 in the demographic transition model (when included)?

Answer: Birth rate below death rate; population decline and aging. Aging populations and below-replacement fertility cause natural decrease, straining resources with more elderly dependents.

Flashcard 7: What defines DTM Stage 2 (early expanding) in terms of birth and death rates?

Answer: High birth rate with rapidly declining death rate; rapid growth. Better sanitation/medicine drops deaths while births stay high.

Flashcard 8: What is demographic momentum (population momentum)?

Answer: Continued growth after fertility drops due to a large young cohort. Large reproductive-age cohorts produce many births despite low fertility.

Flashcard 9: What best characterizes DTM Stage 1 birth and death rates?

Answer: High birth rate and high death rate; low net growth. Pre-industrial societies with minimal population growth.

Flashcard 10: What is the most likely DTM stage for a country with falling death rates but still-high birth rates?

Answer: Stage 2. Stage 2 has declining death rates but fertility remains high.

Flashcard 11: Which population pyramid shape indicates rapid growth with a large youth cohort?

Answer: Expansive (wide base, narrow top). Triangle shape indicates high birth rates and young population.

Flashcard 12: Which population pyramid shape indicates slow or zero growth with similar cohort sizes?

Answer: Stationary (more rectangular). Equal-sized cohorts indicate stable birth and death rates.

Flashcard 13: What is infant mortality rate (IMR) in demographic terms?

Answer: Deaths under age $1$ per $1{,}000$ live births per year. IMR reflects healthcare quality and socioeconomic conditions, serving as a key indicator of infant health risks.

Flashcard 14: Calculate RNI: CBR $= 30$ per $1{,}000$, CDR $= 10$ per $1{,}000$. What is RNI?

Answer: $2\%$ per year. The formula yields positive RNI from high CBR exceeding CDR, typical of developing populations in transition.

Flashcard 15: Identify the pyramid feature most consistent with high infant and child mortality.

Answer: A very steep taper from ages $0$–$4$ to older child cohorts. Sharp narrowing shows many children die before reaching older ages.

Flashcard 16: Identify the demographic term: growth rate equals natural increase plus net migration.

Answer: Overall population growth rate. This term encompasses both intrinsic demographic changes and external migration effects on total population change.

Flashcard 17: What is the dependency ratio conceptually measuring?

Answer: Dependents relative to working-age population. Ratio of young + old to working-age (15-64) population.

Flashcard 18: What is commonly meant by DTM Stage 5 in terms of population change?

Answer: Birth rate falls below death rate; population decline. Some developed nations see fertility drop below replacement.

Flashcard 19: What is the crude death rate (CDR) definition used in population studies?

Answer: Annual deaths per $1{,}000$ people. It quantifies mortality levels uniformly, facilitating analysis of health trends and population dynamics.

Flashcard 20: What does a population pyramid primarily display about a population?

Answer: Age distribution by sex, typically in $5$-year cohorts. Pyramids visualize demographic structure, revealing growth patterns, sex imbalances, and cohort effects.

Flashcard 21: What is the defining pattern of Stage 4 in the demographic transition model?

Answer: Low birth rate and low death rate; stable or slow growth. Modern societies achieve balance with low rates due to advanced healthcare and family planning, stabilizing population.

Flashcard 22: Identify the pyramid feature most consistent with a recent baby boom.

Answer: A bulge in the youngest age cohorts. Large young cohorts indicate recent increase in births.

Flashcard 23: What is demographic momentum in the context of population growth?

Answer: Continued growth after fertility drops due to a young age structure. Large youth cohorts ensure growth even at replacement fertility.

Flashcard 24: If a population pyramid has a narrow base and a large elderly share, what is the likely growth trend?

Answer: Zero or negative growth (aging population). Few births (narrow base) means declining population.

Flashcard 25: Which DTM stage best matches: low death rate, falling birth rate, and continued but slowing growth?

Answer: Stage 3. Classic Stage 3 pattern: mortality transition complete, fertility declining.

Flashcard 26: Which population pyramid shape indicates an aging population with low fertility (expansive, stationary, or constrictive)?

Answer: Constrictive (narrow base, relatively wider middle/older cohorts). Low fertility creates smaller young cohorts than older ones.

Flashcard 27: Which DTM stage best matches a stationary, near-rectangular pyramid in a developed country?

Answer: Stage $4$. Rectangular shape reflects low, stable vital rates.

Flashcard 28: Which DTM stage best matches a constrictive pyramid with aging population and shrinking base?

Answer: Stage $5$. Constrictive shape indicates sub-replacement fertility.

Flashcard 29: If $\text{CBR}=30$ per $1000$ and $\text{CDR}=10$ per $1000$, what is natural increase?

Answer: $20$ per $1000$ (about $2.0\%$ per year, ignoring migration). $30 - 10 = 20$ per $1000$ or $2\%$ annual growth.

Flashcard 30: What does total fertility rate (TFR) measure in a population?

Answer: Average number of children born per woman over her lifetime. TFR estimates completed fertility for a synthetic cohort.

Flashcard 31: What is the formula for rate of natural increase (RNI) when migration is ignored?

Answer: $\text{RNI} = \text{CBR} - \text{CDR}$. Natural increase equals crude birth rate minus crude death rate.

Flashcard 32: What is the dependency ratio conceptually measuring in a population?

Answer: Nonworking-age dependents relative to working-age population. This ratio assesses economic burden, highlighting support needs for youth and elderly relative to the workforce.

Flashcard 33: Identify the population pyramid shape most consistent with rapid growth and high fertility.

Answer: Expansive pyramid (broad base, narrow top). A wide base indicates high youth proportions from elevated births, signaling future expansion potential.

Flashcard 34: What is the defining pattern of Stage 2 in the demographic transition model?

Answer: High birth rate with rapidly declining death rate; rapid growth. Improved healthcare and sanitation reduce mortality while cultural norms keep fertility high, leading to a population surge.

Flashcard 35: What defines DTM Stage 1 (high stationary) in terms of birth and death rates?

Answer: High birth rate and high death rate; minimal net growth. Pre-industrial societies have high mortality offsetting high fertility.

Flashcard 36: What is replacement-level fertility in developed countries?

Answer: Total fertility rate of about $2.1$ children per woman. Accounts for mortality; exactly $2.0$ would mean no growth.

Flashcard 37: What is the dependency ratio in demography intended to compare?

Answer: Dependents (young and old) relative to working-age population. Measures economic burden of non-working age groups.

Flashcard 38: What best characterizes DTM Stage 3 changes in birth rate and growth?

Answer: Birth rate declines; death rate low; growth slows. Urbanization and education reduce desired family size.

Flashcard 39: Identify the population pyramid shape most consistent with population decline and aging.

Answer: Constrictive pyramid (narrow base, wider older cohorts). A tapering base shows low fertility, leading to an inverted shape with more elderly and overall shrinkage.

Flashcard 40: Which demographic transition stage best matches an expansive pyramid with falling death rates?

Answer: Stage 2. Rapid growth from declining mortality and high fertility creates a broad-based pyramid typical of early industrialization.

Flashcard 41: What is the replacement-level fertility value for developed populations?

Answer: Approximately $2.1$ children per woman. This threshold ensures population stability by compensating for infant mortality and non-reproductive individuals.

Flashcard 42: Which population pyramid shape indicates population decline with fewer young people than middle-aged?

Answer: Constrictive (narrow base, larger middle/older cohorts). Inverted shape shows declining births and aging population.

Flashcard 43: What is the demographic transition model (DTM) intended to describe about a country over time?

Answer: Shifts in birth and death rates as a country industrializes. DTM tracks how population dynamics change with industrialization.

Flashcard 44: Which population pyramid shape indicates population decline and aging?

Answer: Constrictive (narrow base, wider middle/older cohorts). Inverted shape shows fewer births than older cohorts.

Flashcard 45: What is the demographic transition model (DTM)?

Answer: A staged model linking development to birth/death rates and growth. Links population growth patterns to economic development stages.

Flashcard 46: Calculate RNI if $\text{CBR} = 30$ per $1000$ and $\text{CDR} = 10$ per $1000$ (ignore migration).

Answer: $20$ per $1000$ per year (about $2.0\%$ per year). RNI = $30 - 10 = 20$ per $1000$ (divide by $10$ for percent).

Flashcard 47: Which population pyramid shape indicates rapid growth with high fertility?

Answer: Expansive pyramid with a wide base. Triangle shape indicates many births and young population.

Flashcard 48: Identify the most likely cause of a sudden notch affecting mainly males in one adult age cohort.

Answer: War or sex-specific mortality concentrated in that cohort. Wars disproportionately kill young adult males.

Flashcard 49: Identify the pyramid feature most consistent with high infant mortality.

Answer: A steep drop from the youngest cohort to the next cohort. Many infants die before reaching age 1-4 cohort.

Flashcard 50: What defines DTM Stage 4 (low stationary) in terms of birth and death rates?

Answer: Low birth rate and low death rate; stable or slow growth. Post-industrial equilibrium with both rates at low levels.

Flashcard 51: Which demographic transition stage is defined by falling death rate with high birth rate?

Answer: Stage $2$ (transitional/early industrial). Death rates drop first, creating rapid population growth.

Flashcard 52: Which demographic transition stage best matches a constrictive pyramid with fertility below replacement?

Answer: Stage 5. Sub-replacement fertility inverts the structure, with fewer young people causing decline and increased aging.

Flashcard 53: What is a population pyramid and what two variables does it display?

Answer: Age distribution by sex, usually as horizontal bars by cohort. Males left, females right; width shows cohort size.

Flashcard 54: Which demographic transition stage is often described as very low birth rate causing decline?

Answer: Stage $5$ (population decline). Birth rate falls below death rate, causing negative growth.

Flashcard 55: Identify the most likely interpretation of a large bulge in ages $15$–$24$ on a population pyramid.

Answer: A past baby boom or cohort effect entering young adulthood. Echo effect from high births $15$-$24$ years ago.

Flashcard 56: What is population momentum in demography?

Answer: Continued growth after fertility falls due to a large young cohort. A youthful age structure sustains growth through high reproductive potential despite reduced birth rates.

Flashcard 57: What is the formula for population growth rate when net migration is included?

Answer: $\text{Growth rate} = (\text{CBR} - \text{CDR}) + \text{NMR}$. Total growth includes natural increase plus net migration rate.

Flashcard 58: What is the formula for population growth rate using crude rates?

Answer: $\text{Growth rate} = \text{CBR} - \text{CDR}$ (ignoring migration). Natural increase equals births minus deaths per 1000 population.

Flashcard 59: In the DTM, what key change most directly drives the death-rate drop in Stage $2$?

Answer: Improved sanitation, nutrition, and medical/public health measures. These improvements reduce disease and increase survival rates.

Flashcard 60: Which DTM stage best matches an expansive pyramid with a very wide base and narrow top?

Answer: Stage $2$. Expansive pyramids match high birth, declining death rates.

Flashcard 61: What is the approximate replacement-level fertility in developed countries?

Answer: About $2.1$ births per woman. Accounts for infant mortality; exactly $2.0$ would mean decline.

Flashcard 62: What best characterizes DTM Stage 5 population change?

Answer: Birth rate below death rate; zero or negative natural increase. Very low fertility leads to population decline without immigration.

Flashcard 63: Which population pyramid shape indicates rapid growth and high fertility (expansive, stationary, or constrictive)?

Answer: Expansive (broad base, narrow top). Wide base from high fertility; narrows due to mortality.

Flashcard 64: What two rates primarily determine a population's rate of natural increase (RNI)?

Answer: Crude birth rate and crude death rate. RNI measures population growth from births minus deaths only.

Flashcard 65: What is the formula for rate of natural increase (RNI) using birth and death rates?

Answer: $\text{RNI} = \text{CBR} - \text{CDR}$. Subtracts crude death rate from crude birth rate for natural growth.

Flashcard 66: Which demographic transition stage has low birth rate and low death rate with stable population?

Answer: Stage $4$ (postindustrial). Both rates stabilize at low levels, growth near zero.

Flashcard 67: What is life expectancy at birth in population health statistics?

Answer: Average expected years of life for a newborn given current rates. It projects survival based on current age-specific mortality, influencing policy on aging and healthcare.

Flashcard 68: Which demographic transition stage best matches a rectangular pyramid with low birth and death rates?

Answer: Stage 4. Low, balanced rates produce even cohort sizes, indicating zero or minimal natural increase in mature economies.

Flashcard 69: What is the demographic transition model (DTM) used to describe in populations?

Answer: How birth and death rates change with economic development over time. DTM shows population patterns as societies industrialize and modernize.

Flashcard 70: What best characterizes DTM Stage 4 birth and death rates?

Answer: Low birth rate and low death rate; stable or slow growth. Post-industrial equilibrium with near-zero natural increase.

Flashcard 71: Which DTM stage typically has the highest rate of natural increase (RNI)?

Answer: Stage 2. Maximum gap between births and deaths occurs in early transition.

Flashcard 72: What best characterizes DTM Stage 2 changes in death rate and growth?

Answer: Death rate falls sharply; birth rate stays high; rapid growth. Improved sanitation/medicine drops deaths before births decline.

Flashcard 73: What is the defining pattern of Stage 3 in the demographic transition model?

Answer: Declining birth rate with low death rate; growth slows. Urbanization and education lower birth rates as death rates stabilize, moderating the expansion.

Flashcard 74: Identify the pyramid feature most consistent with a recent baby boom.

Answer: A bulge in younger cohorts (wider bars at low ages). Baby boom creates wider bars at those birth years.

Flashcard 75: Calculate RNI: CBR $= 12$ per $1{,}000$, CDR $= 14$ per $1{,}000$. What is RNI?

Answer: $-0.2\%$ per year. Negative RNI results when CDR surpasses CBR, indicating natural decrease common in aging societies.

Flashcard 76: What is the crude birth rate (CBR) definition used in population studies?

Answer: Annual births per $1{,}000$ people. This metric provides a standardized measure of fertility, allowing comparisons across populations regardless of size.

Flashcard 77: What is a population pyramid designed to display about a population at a given time?

Answer: Age distribution by sex (typically in $5$-year cohorts). Shows population structure with males on left, females on right.

Flashcard 78: What is the defining pattern of Stage 1 in the demographic transition model?

Answer: High birth rate and high death rate; low net growth. Pre-industrial societies maintain equilibrium through balanced high rates, resulting in minimal population change.

Flashcard 79: In the DTM, what social changes commonly contribute to the birth-rate drop in Stage $3$?

Answer: Contraception, female education/employment, urbanization, lower infant mortality. These factors reduce desired family size and enable family planning.

Flashcard 80: State the formula for the rate of natural increase (RNI) using CBR and CDR.

Answer: $\text{RNI} = \frac{\text{CBR} - \text{CDR}}{10}$ (percent per year). Dividing the difference by 10 converts the per-thousand rates to a percentage, indicating natural population change.

Flashcard 81: Which demographic transition stage is defined by falling birth rate with low death rate?

Answer: Stage $3$ (industrial/late industrial). Birth rates decline to match already-low death rates.

Flashcard 82: Identify the population pyramid shape most consistent with stable growth and low fertility.

Answer: Stationary/rectangular pyramid (similar cohort widths). Uniform widths reflect balanced birth and death rates, maintaining constant population size over time.

Flashcard 83: What is the dependency ratio intended to capture about a population?

Answer: Burden on working-age group from young and old dependents. Ratio of non-working ages to working-age population.

Flashcard 84: What demographic transition stage has high birth rate and high death rate with slow growth?

Answer: Stage $1$ (preindustrial). Both rates are high, resulting in minimal population change.