2.3 Flash Cards
Study
What Factors affect population growth rates?
- Sex Ratio (# females vs # males)
- Age Structure (# of females at reproductive age in the cohort)
- Generation Time (age at which females reproduce)
What is the Sex Ratio?
The number of females vs the number of males in a population
What is Age Structure?
The number of females at reproductive age in a population
What is Generation Time?
The age at which females reproduce in a population
What concerns are there with human population growth?
- Increased extraction of resources from the environment
- Burning of fossil fuels
- Increased use of fresh water
- Increased ecological impact (destruction of forests, etc)
- Increased fishing and hunting
- Spread of Invasive species
- Transmission of diseases
How many stages of demographic transition are there?
Five
Stage One of Demographic Transition
Birth Rate - High
Death Rate- High
Natural Increase- Stable or Slow Increase
Population Pyramid- Curves inward with a point at the top
Stage Two of Demographic Transition
Birth Rate- High
Death Rate- Falls Rapidly
Natural Increase- Rapid Increase
Population Pyramid- Equilateral triangle shape
Stage Three of Demographic Transition
Birth Rate- Falling
Death Rate- Falls more slowly
Natural Increase- Increase slows down
Population Pyramid- Equilateral triangle with a rectangle as the base
Stage Four of Demographic Transition
Birth Rate- Low
Death Rate- Low
Natural Increase- Falling then stable
Population Pyramid- Fingernail shaped
Stage Five of Demographic Transition
Birth Rate- Yet to be seen (Possibly falling further, possibly rising again)
Death Rate- Low
Natural Increase- Little Change
Population Pyramid- Fingernail shaped with a flared base
What type of programs would lead a Population from Stage 1 to Stage 4 of Demographic Transition?
- Education
- Women Empowerment
- Labor Market
- Family Planning
- Maternal and Child Health
Population Growth Formula
[(birth-death) / (population size)] * 100
What sex is more important when predicting off-spring?
Female
What will happen to resources with a bigger population size?
Resources will be deplenished
Are the births even or uneven when comparing developed and under developed countries?
Births are not even; 90% are in developed countries
If there are more females in a population then the size of the population will..
Grow faster compared to populations for fewer females and more males
What does a shorter generation gap mean for population growth?
Faster population growth
Demographic Transition
Describes the changes in population size, the structure caused by changes in birth rate, death rate and by migration
Urbanization?
The increase in the proportion of people living in towns and cities vs rural areas
Birth Rate?
The number of births per thousand per year
Death Rate?
The number of deaths per thousand per year
Growth Rate?
The rate or speed at which the number of organisms in a population increase/ decreases
Infant Mortality and importance as a demographic stat?
The death of a baby that occurs between the time of birth and one year. It is used as a measure of the health and wellness of a community.