Vocab
State the definition of limiting resource.
A limiting resource is a resource that a population cannot live without and that occurs in quantites lower than the population would require to increase in size.
state the type of species that has an equal distribution of individuals at a variety of values
Niche Generalists
Explain how a population oscillates.
Some Populations experience recurring cycles of overshoots and diebacks that leads to a pattern of oscillations around the carrying capacity of their environment.
Explain the difference between immigration and emigration.
Immigration is the movement of the people in. Emmigration is the movement of people exiting.
State the formula to determine a population's doubling time.
70/ percentage population growth = populations doubling time
State what the demographers studies.
Demographers study human populations and population trends.
state the type of species that persists when environmental conditions remain relatively constant or if the food source they specialize on is abundant
Niche Specialists
Name a density-dependant factor.
Any factor that depends on the size of the population. Such as food, water, etc.
Name the life expectancy of the United States.
The average life expectancy of the United States is 78 years.
State the demographic transition stage where the population is stable.
Stage three which is the Industrialized stage.
State the defintion of doubling time.
Doubling time is the number of years it takes a population to double.
explain the correlation of overshoot and dieback
Some populations experience an overshoot of the carrying capacity and a subsequent dieback.
Name a density-independant factor.
Any factor that has the same effect regardless of population size. Such as hurricanes, floods, fires, etc.
State factors that influence total fertility rate.
Access to family planning services, education, the age a woman has her first child, and other social and economic factors.
State the IPAT equation.
impact=population x affluence x technology
State the definition of population momentum.
Population momentum is continued population growth after growth reduction measures have been implemented.
Explain the difference between K-selected species and r-selected species
K-selected species have a low intirnisc growth rate that causes slow increases in population, while r-selected has a high intrinsic growth rate which causes rapid increase in the population.
Explain why the logistic growth model has a S-shaped curve.
A population beings experiencing exponential growth. As the population becomes larger, resources become more scarce, and the growth rate slows. When the population size reaches the carrying capacity of the environment, growth stops.
State the formula for the population growth rate.
National Population % growth rate =
(CBR+immigration)-(CDR+emigration) / 10
State the theory of demographic transition.
The theory states that a country moves from high to lower birth and death rates as development occurs and that country moves from a preindustrial to an industrialized economic system.
State the definition of fecundity.
Fecundity is the ability to produce an abundance of offspring.
What type of survivorship curve are humans?
Humans are a Type 1 survivorship curve.
Explain the reasoning behind the J-shaped curve for the exponential growth model.
When populations are not limited by resources, their growth can be very rapid. This factor and the increase of births rates creates a J-shaped curve.
State Thomas Malthus's hypothesis
The human population size will eventually exceed the food supply. This is because the human population grows exponentially and the food supply grows linearly.
Name the stages of population growth.
Preindustrial, industrializing, industrialized, preindustrial.