Chapter 5: Populations

Unusual weather

________ and natural disasters can act as density- independent limiting factors.

Competition

________ depends on population density.

demographic transition

The ________ is complete when the birthrate meets the death rate.

predation

Limiting factors include competition for resources, ________, parasitism and disease, unusual weather, and natural disasters.

Density independent

A(n) ________ limiting factor is a limiting factor that affects all populations in similar ways, regardless of population size

Demography

Looks at characteristics of human populations and tries to explain how those populations will change over time

Demographic transition

In the ________, a population changes from having high birth rates and death rates to having low birth rates and death rates

Ex

when people kill too many cod fish, the cod population falls; if people killed fewer cod, the population could rise again

Geographic range

A population’s _______ describes the spaces where it lives

Population density

The number of individuals of a species per unit area

Population distribution

Describes how organisms are spread across their range

Growth rate

A population’s _______ tells you if the population size is getting bigger, smaller, or staying the same

Age structure

The _______ of a population describes the number of males and females of each age in the population

Immigration

When individuals move into a population’s range, the process is called _______

Emigration

When individuals move out of the range, the process is called _______

Exponential growth

A growth pattern in which the individuals in a population reproduce at a constant rate

Logistic growth

A growth pattern in which a population’s growth rate slows or stops, following a period of exponential growth

Carrying capacity

The largest number of individuals of a population that a given environment can support

Limiting factor

Any factor that controls the size of a population

Density-dependent limiting factor

A limiting factor that depends on population density

Density-independent limiting factor

A limiting factor that affects all populations in similar ways, regardless of population size

Demography

The scientific study of human populations

Demographic transition

A change in a population from high birth rates and death rates to low birth rates and death rates