MCAT Psychological Social Foundations Flashcards: 9b Fertility Mortality Population Growth

What this deck covers

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

How to use these flashcards

Work through these flashcards in short sessions. Try to answer each prompt before flipping the card, then revisit any cards you miss until the explanation feels automatic.

Flashcard 1: Identify the demographic transition stage with low birth and low death rates.

Answer: Stage $4$ (postindustrial). Population stabilizes with minimal natural increase.

Flashcard 2: State the formula for natural increase rate (ignoring migration).

Answer: r = rac{ ext{CBR} - ext{CDR}}{1000}. Converts per-thousand rates to decimal growth rate.

Flashcard 3: Identify the demographic transition stage with falling birth rates and low death rates.

Answer: Stage $3$ (industrial). Birth rates decline following earlier mortality decline.

Flashcard 4: What is the definition of the crude death rate (CDR) in demography?

Answer: Deaths per $1{,}000$ people per year. Measures deaths relative to total population size annually.

Flashcard 5: What is replacement-level fertility in developed countries?

Answer: Approximately $2.1$ births per woman. Accounts for infant mortality requiring slightly above 2.

Flashcard 6: What is the definition of the crude birth rate (CBR) in a population?

Answer: Annual live births per $1{,}000$ people. Standardizes the number of live births annually to a rate per thousand individuals in the total population for comparability across groups.

Flashcard 7: Identify the demographic transition stage with high birth and high death rates.

Answer: Stage $1$ (preindustrial). Minimal population growth due to balanced rates.

Flashcard 8: State the formula for infant mortality rate (IMR) per $1000$ live births.

Answer: $\text{IMR}=\frac{\text{deaths under age }1}{\text{live births}}\times 1000$. First year of life has highest mortality risk.

Flashcard 9: What is the rule of $70$ for doubling time using growth rate $r\%$?

Answer: $t_d\approx\frac{70}{r\%}$. Approximates the time for population doubling by dividing 70 by the annual percentage growth rate, derived from logarithmic growth properties.

Flashcard 10: Which population pyramid shape is most consistent with a stable or slow-growing population?

Answer: More rectangular (similar cohort sizes across ages). Equal birth/death rates produce uniform age distribution.

Flashcard 11: Which demographic transition stage is characterized by falling birth rates and low death rates?

Answer: Stage $3$. Population growth slows as fertility declines with development.

Flashcard 12: What is the definition of the sex ratio at birth used in demography?

Answer: Males per $100$ females at birth. Natural ratio is about $105:100$; deviations suggest sex selection.

Flashcard 13: What is the definition of population growth rate including net migration?

Answer: Births minus deaths plus net migration (as a rate). Incorporates both natural increase (births minus deaths) and migration balance to determine the overall rate of population change.

Flashcard 14: What is the definition of the crude birth rate (CBR) in a population?

Answer: Annual live births per $1{,}000$ people. Measures births relative to total population size annually.

Flashcard 15: What is the formula for population growth rate including net migration?

Answer: Growth rate $=$ RNI $+$ net migration rate. Total growth includes both natural increase and migration.

Flashcard 16: Which DTT stage is characterized by high birth rate and high death rate?

Answer: Stage $1$ (preindustrial). Low population growth due to high mortality offsetting high fertility.

Flashcard 17: What is the Rule of $70$ approximation for doubling time?

Answer: $t_d \approx \frac{70}{100r}$ when $r$ is expressed as a decimal. Quick estimate: divide 70 by percentage growth rate.

Flashcard 18: Which demographic transition stage has low birth rates and low death rates with stable population size?

Answer: Stage $4$. Post-industrial equilibrium with zero population growth.

Flashcard 19: What is the definition of the rate of natural increase (RNI)?

Answer: Birth rate minus death rate (excluding migration). Captures intrinsic population dynamics by subtracting the death rate from the birth rate, isolating growth from vital events excluding migration.

Flashcard 20: Identify the demographic transition stage with falling death rates but high birth rates.

Answer: Stage $2$ (transitional/early industrial). Rapid population growth begins as mortality declines.

Flashcard 21: State the approximate formula for annual growth rate (%) using CBR and CDR only.

Answer: rac{ ext{CBR} - ext{CDR}}{10}. Dividing by $10$ converts per $1{,}000$ rates to percentages.

Flashcard 22: State the formula for overall population growth rate including net migration.

Answer: rac{( ext{CBR}- ext{CDR})+ ext{net migration}}{10} (percent/yr). Combines natural increase with migration effects.

Flashcard 23: What is the crude death rate (CDR) definition?

Answer: Annual deaths per $1000$ people in the total population. Key indicator of population health and healthcare quality.

Flashcard 24: What is the definition of crude birth rate (CBR)?

Answer: Annual live births per $1000$ people in the population. Standardized per 1000 people for easy comparison.

Flashcard 25: What is the definition of the total fertility rate (TFR)?

Answer: Expected births per woman over her lifetime. Sums age-specific fertility rates to estimate the average number of children a woman would bear if she experienced current rates throughout her reproductive years.

Flashcard 26: Identify the term for a population pyramid with a wide base and narrow top.

Answer: Expansive pyramid (rapid growth; high fertility; young population). Common in developing countries with high birth rates.

Flashcard 27: Which demographic transition stage has high birth rates and high death rates?

Answer: Stage $1$. Pre-industrial societies with minimal population growth.

Flashcard 28: What is the definition of the crude death rate (CDR) in a population?

Answer: Annual deaths per $1{,}000$ people. Provides a standardized measure of annual mortality by expressing deaths per thousand individuals in the population.

Flashcard 29: What does replacement-level fertility mean in developed countries?

Answer: Approximately $2.1$ births per woman. Represents the fertility level needed to maintain population size, accounting for infant mortality and a slight bias toward male births in developed nations.

Flashcard 30: What is life expectancy at birth?

Answer: Average years a newborn is expected to live. Calculates the mean lifespan assuming current age-specific mortality rates persist, serving as an indicator of overall population health.

Flashcard 31: What is life expectancy at birth?

Answer: Average years a newborn is expected to live given current rates. Reflects overall health conditions and mortality patterns.

Flashcard 32: What is the formula for rate of natural increase (RNI) using crude rates?

Answer: rac{ ext{CBR}- ext{CDR}}{10} percent per year. Dividing by $10$ converts per thousand to percentage.

Flashcard 33: What does carrying capacity $K$ represent in population ecology?

Answer: Maximum sustainable population size in an environment. Denotes the upper limit of population size supported by available resources, leading to stabilized growth in logistic models.

Flashcard 34: What is the infant mortality rate (IMR)?

Answer: Deaths under age $1$ per $1{,}000$ live births per year. Key indicator of healthcare quality and child survival.

Flashcard 35: What is the maternal mortality ratio (MMR) typically reported as?

Answer: Maternal deaths per $100{,}000$ live births. Reflects maternal healthcare access and quality.

Flashcard 36: What is demographic transition model Stage $4$ characterized by?

Answer: Low birth rate and low death rate (stable/slow growth). Reflects mature economies where low fertility matches low mortality due to education, contraception, and economic shifts, yielding equilibrium.

Flashcard 37: What is demographic transition theory (DTT) describing at a high level?

Answer: Shift from high to low birth/death rates with development. Links modernization to demographic changes.

Flashcard 38: What is the replacement-level fertility in developed countries (approximate TFR)?

Answer: About $2.1$ children per woman. Accounts for infant mortality; maintains stable population size.

Flashcard 39: What is life expectancy at birth?

Answer: Average years a newborn is expected to live given current mortality. Assumes current age-specific death rates remain constant.

Flashcard 40: What is demographic transition model (DTM) Stage $4$ characterized by?

Answer: Low birth and death rates; stable or slow growth. Post-transition equilibrium with low vital rates.

Flashcard 41: State the formula for exponential population growth using $r$ and $N$.

Answer: $\frac{dN}{dt}=rN$. Models unbounded growth where the rate of change is proportional to current population size via the intrinsic growth rate $r$.

Flashcard 42: What is the definition of the crude birth rate (CBR) in demography?

Answer: Live births per $1{,}000$ people per year. Measures births relative to total population size annually.

Flashcard 43: What is the definition of net migration rate?

Answer: Immigrants minus emigrants per $1{,}000$ people per year. Positive values indicate net immigration; negative means net emigration.

Flashcard 44: What is the definition of the infant mortality rate (IMR)?

Answer: Deaths under age $1$ per $1{,}000$ live births. Key indicator of healthcare quality and maternal/child health.

Flashcard 45: Identify the growth pattern when population size increases by a constant proportion per unit time.

Answer: Exponential growth. Population multiplies by same factor each time period.

Flashcard 46: What is replacement-level fertility in developed countries (approximate TFR)?

Answer: About $2.1$ children per woman. Accounts for infant mortality; higher in developing countries.

Flashcard 47: State the logistic growth equation using intrinsic rate $r$ and carrying capacity $K$.

Answer: $\frac{dN}{dt}=rN\left(\frac{K-N}{K}\right)$. Incorporates density dependence by modulating growth rate $r$ with the fraction of carrying capacity $K$ remaining unoccupied.

Flashcard 48: Calculate growth rate (%): CBR $= 30$, CDR $= 10$, net migration $= 0$.

Answer: 2.0\text{%}. Using $(30-10)/10 = 2.0\%$ with no migration effect.

Flashcard 49: In DTT Stage $3$, what happens to birth rates and why is growth slowed?

Answer: Birth rate declines (contraception, urbanization, education). Social changes reduce desired family size.

Flashcard 50: If $\text{CBR}=18$ and $\text{CDR}=8$ (per $1{,}000$), what is $\text{RNI}(\%)$?

Answer: $1.0\%$. Applies the RNI formula: subtract CDR from CBR and divide by 10 to express natural growth as a percentage.

Flashcard 51: State the demographic balancing equation for population change.

Answer: $\Delta N=(B-D)+(I-E)$. Accounts for population change by balancing natural increase (births minus deaths) with net migration (immigrants minus emigrants).

Flashcard 52: Identify the term for births minus deaths in a population (ignoring migration).

Answer: Natural increase. Excludes migration effects; also called rate of natural increase.

Flashcard 53: Calculate RNI: If CBR is $30$ and CDR is $10$, what is RNI in percent per year?

Answer: $2.0\%$ per year. RNI = rac{30-10}{10} = rac{20}{10} = 2.0\%

Flashcard 54: What is the definition of the dependency ratio?

Answer: Ratio of dependents to working-age population. Measures economic burden of non-working age groups.

Flashcard 55: Which age-structure shape (pyramid, column, inverted) indicates rapid growth?

Answer: Pyramid-shaped age structure. Wide base indicates high birth rates and young population.

Flashcard 56: What is the definition of the crude birth rate (CBR) in demography?

Answer: Live births per $1{,}000$ people per year. Measures births relative to total population size annually.

Flashcard 57: State the formula for natural increase rate (NIR) using CBR and CDR.

Answer: rac{ ext{CBR}- ext{CDR}}{10} (percent per year). Converts per-thousand difference to percentage growth.

Flashcard 58: What is the definition of infant mortality rate (IMR)?

Answer: Deaths under age 1 per $1000$ live births in a year. Specifically tracks deaths in the first year of life.

Flashcard 59: State the formula for infant mortality rate (IMR).

Answer: $\text{IMR}=\frac{\text{deaths under age 1}}{\text{live births}}\times 1{,}000$. Determines the rate by dividing infant deaths by live births and scaling by 1,000, reflecting healthcare and socioeconomic conditions.

Flashcard 60: Calculate growth rate: If RNI is $1.5\%$ and net migration is $-0.5\%$, what is total growth?

Answer: $1.0\%$ per year. Growth $= 1.5\% + (-0.5\%) = 1.0\%$ per year

Flashcard 61: What is demographic transition model (DTM) Stage $2$ characterized by?

Answer: High birth rate with rapidly falling death rate; rapid growth. Medical advances reduce mortality before fertility declines.

Flashcard 62: Calculate growth rate (%): $B=50{,}000$, $D=30{,}000$, $I=5{,}000$, $E=10{,}000$, $N=1{,}000{,}000$.

Answer: 1.5\text{%}. $(50{,}000-30{,}000+5{,}000-10{,}000)/1{,}000{,}000 \times 100 = 1.5\%$

Flashcard 63: Which growth pattern is described by $\frac{dN}{dt} = rN$?

Answer: Exponential growth. Growth rate proportional to current population size.

Flashcard 64: Which option best describes population momentum after fertility drops to replacement?

Answer: Continued growth due to a large cohort entering reproductive ages. Young age structure sustains growth despite low fertility.

Flashcard 65: State the formula for crude death rate (CDR) using deaths and total population.

Answer: $\text{CDR}=\frac{\text{deaths}}{\text{total population}}\times 1{,}000$. Calculates the ratio of annual deaths to total population, multiplied by 1,000 to facilitate cross-population comparisons.

Flashcard 66: What is the typical shape of an exponential growth curve over time?

Answer: J-shaped curve. Reflects accelerating growth without constraints, resulting in a curve that rises sharply upward resembling the letter J.

Flashcard 67: What is life expectancy at birth in demographic terms?

Answer: Avg. years a newborn is expected to live. Reflects overall health and development conditions.

Flashcard 68: What is the definition of fertility rate in demography?

Answer: Number of live births in a population per unit time. Measures reproductive output of a population over time.

Flashcard 69: What is the definition of mortality rate in demography?

Answer: Frequency of death in a population per unit time. Encompasses all causes of death in a population.

Flashcard 70: Calculate NIR: If $ext{CBR}=18$ and $ext{CDR}=8$, what is the NIR (percent per year)?

Answer: $1.0\%$ per year. $(18-8)/10 = 10/10 = 1.0\%$ natural increase.

Flashcard 71: Which demographic transition stage is characterized by birth rates below death rates (population decline)?

Answer: Stage $5$. Some developed countries face aging populations and decline.

Flashcard 72: Using the rule of $70$, estimate doubling time (years) for a population growing at 2\text{%}/year.

Answer: $35$ years. Rule of $70$: doubling time $\approx 70/\text{growth rate}$.

Flashcard 73: What is the total fertility rate (TFR)?

Answer: Average number of children a woman is expected to have. Calculated over her entire reproductive lifespan.

Flashcard 74: What is the definition of the crude death rate (CDR) in demography?

Answer: Deaths per $1{,}000$ people per year. Measures deaths relative to total population size annually.

Flashcard 75: State the formula for RNI as a percent using CBR and CDR (per $1{,}000$).

Answer: $\text{RNI}(\%)=\frac{\text{CBR}-\text{CDR}}{10}$. Converts the difference between per-thousand rates to a percentage by dividing by 10, enabling assessment of natural population growth.

Flashcard 76: Which population pyramid shape is most consistent with rapid population growth?

Answer: Broad base, narrow top (triangular pyramid). High fertility creates large young cohorts.

Flashcard 77: What is demographic transition theory (DTT) in one sentence?

Answer: Model of shifting birth/death rates as societies industrialize and develop. Explains population changes during economic development.

Flashcard 78: What is the crude birth rate (CBR) definition?

Answer: Annual births per $1000$ people in the total population. Standardized measure allowing comparison between populations.

Flashcard 79: Calculate doubling time: If a population grows at $2\%$ per year, what is the approximate doubling time?

Answer: About $35$ years (rule of $70$: $70\div 2$). Rule of 70 estimates doubling time from growth rate.

Flashcard 80: What is the replacement-level fertility in developed populations (approximate TFR)?

Answer: About $2.1$ children per woman. Accounts for infant mortality; maintains stable population.

Flashcard 81: What is the definition of the crude death rate (CDR) in a population?

Answer: Annual deaths per $1{,}000$ people. Measures deaths relative to total population size annually.

Flashcard 82: In DTT Stage $2$, which change is the primary driver of rapid population growth?

Answer: Death rate falls while birth rate remains high. Medical advances reduce mortality before fertility declines.

Flashcard 83: What is the definition of net migration rate?

Answer: Immigrants minus emigrants per $1{,}000$ people. Positive values indicate net immigration; negative means net emigration.

Flashcard 84: What is population momentum?

Answer: Continued growth after fertility declines due to a young age structure. Large cohorts of reproductive age maintain growth despite lower TFR.

Flashcard 85: What is the definition of the general fertility rate (GFR)?

Answer: Births per $1{,}000$ women ages $15$–$44$ per year. Focuses on reproductive-age women for more accurate fertility measure.

Flashcard 86: What is the infant mortality rate (IMR) definition?

Answer: Deaths under age $1$ per $1000$ live births in a year. Critical indicator of maternal and infant healthcare quality.

Flashcard 87: What is a population pyramid primarily used to display?

Answer: Age and sex structure of a population. Visualizes demographic composition as horizontal bars.

Flashcard 88: What is the definition of mortality rate in a population?

Answer: Number of deaths per unit population in a given time period. Measures population loss through death per time unit.

Flashcard 89: What is the definition of migration rate in population change?

Answer: Net migration per $1{,}000$ people per year. Difference between immigration and emigration rates.

Flashcard 90: What does carrying capacity $K$ represent in logistic growth?

Answer: Maximum sustainable population size given environmental limits. Resources and space limit population growth.

Flashcard 91: Identify the concept: population continues to grow after fertility drops to replacement due to age structure.

Answer: Population momentum. Large reproductive-age cohorts sustain growth temporarily.

Flashcard 92: Which population pyramid feature most strongly suggests population decline?

Answer: Narrow base relative to middle cohorts. Low fertility reduces younger cohort sizes.

Flashcard 93: What is the definition of crude death rate (CDR)?

Answer: Annual deaths per $1000$ people in the population. Standardized per 1000 people for easy comparison.

Flashcard 94: What is the definition of the total fertility rate (TFR)?

Answer: Average number of children per woman over her lifetime. Indicates reproductive output per woman in a population.

Flashcard 95: What is the definition of the infant mortality rate (IMR)?

Answer: Deaths under age $1$ per $1{,}000$ live births. Measures early childhood survival by quantifying deaths in the first year of life relative to every thousand live births.

Flashcard 96: What is the definition of morbidity (as distinct from mortality)?

Answer: Incidence or prevalence of disease or disability in a population. Measures illness burden, not death.

Flashcard 97: What is the definition of natural increase (or natural decrease)?

Answer: Births minus deaths, excluding migration. Positive when births exceed deaths, negative when deaths exceed births.

Flashcard 98: What is the definition of population doubling time?

Answer: Time required for a population to double in size at a constant $r$. Assumes exponential growth continues unchanged.

Flashcard 99: Which DTT stage is characterized by falling death rate with still-high birth rate?

Answer: Stage $2$ (early industrial; rapid population growth). Improved sanitation and medicine reduce deaths before births decline.

Flashcard 100: What is replacement-level fertility in developed countries (ignoring migration)?

Answer: Approximately $2.1$ births per woman. Accounts for infant mortality; maintains stable population size.