Ch.4 Guided Reading
Population: Group of organisms of the same species living in a particular region.
Key Properties of Populations:
1. Abundance
2. Birth Rates
3. Death Rates
4. Growth Rates
5. Age Structure
Demographics: Statistical studies of human populations.
Calculating Growth Rates:
Take the present population of a region for the current year; then take the population of that same region for a year before the current and divide by past years population multiply by 100 then divide by the difference in years.
Ex,
{[(Present Population-Past Population)/past population]*100}/difference in years
Present= 270,000 (2015)
Past= 150,000 (2000)
{[(270,000-150,000)/150,000]*100}/15= 5.3%
Age Structures:
The four main types of diagrams show- Rapid Growth, Slow Growth, Zero Growth, and Negative Growth.
Human populations have grown due to medical advancement, technology, and innovations.
Doubling Time: The number of years it takes for a population to double. It is calculated through the rule of 70; which means 70 divided by the annual growth rate.
A logistic growth rate illustrates how a population can start from a small amount and continue to get bigger exponentially until the population hits the carrying capacity which will force the growth rate to stabilize.
Three major stages of demographic transition are:
1. Preindustrial- where birth rates and death rates are high, therefore growth rate are stable.
2. Transitional- where birthrates are high and death rates are low, therefore growth rates are high.
3. Post-industrial- where birth rates and death rates are low hence the growth rate stabilizes again.
Two things that determine human impact on the environment are the population and the needed resources to sustain that population hence agriculture.
The amount of people that Earth can sustain depends largely on the exploitation of resources that is available and land available to produce food for the population.
Medical advancement through technology can have its' drawbacks such as allowing viruses to keep adapting to the medicine and ultimately create an epidemic that can wipe out a lot of the human population.
Life expectancy is the average age that adults reach before they die.
Zero population growth can be achieved if the birthrates and the death rates are equal; however it is not always true that is why governments use immigration to raise their population.
Key Properties of Populations:
1. Abundance
2. Birth Rates
3. Death Rates
4. Growth Rates
5. Age Structure
Demographics: Statistical studies of human populations.
Calculating Growth Rates:
Take the present population of a region for the current year; then take the population of that same region for a year before the current and divide by past years population multiply by 100 then divide by the difference in years.
Ex,
{[(Present Population-Past Population)/past population]*100}/difference in years
Present= 270,000 (2015)
Past= 150,000 (2000)
{[(270,000-150,000)/150,000]*100}/15= 5.3%
Age Structures:
The four main types of diagrams show- Rapid Growth, Slow Growth, Zero Growth, and Negative Growth.
Human populations have grown due to medical advancement, technology, and innovations.
Doubling Time: The number of years it takes for a population to double. It is calculated through the rule of 70; which means 70 divided by the annual growth rate.
A logistic growth rate illustrates how a population can start from a small amount and continue to get bigger exponentially until the population hits the carrying capacity which will force the growth rate to stabilize.
Three major stages of demographic transition are:
1. Preindustrial- where birth rates and death rates are high, therefore growth rate are stable.
2. Transitional- where birthrates are high and death rates are low, therefore growth rates are high.
3. Post-industrial- where birth rates and death rates are low hence the growth rate stabilizes again.
Two things that determine human impact on the environment are the population and the needed resources to sustain that population hence agriculture.
The amount of people that Earth can sustain depends largely on the exploitation of resources that is available and land available to produce food for the population.
Medical advancement through technology can have its' drawbacks such as allowing viruses to keep adapting to the medicine and ultimately create an epidemic that can wipe out a lot of the human population.
Life expectancy is the average age that adults reach before they die.
Zero population growth can be achieved if the birthrates and the death rates are equal; however it is not always true that is why governments use immigration to raise their population.