Chapter 5-6 Flashcards
(52 cards)
Three important characteristics of a population
Geographic Distribution (range): Area inhabited.
Population Density: Number of individuals per unit area.
Growth Rate: The number of individuals either increase or decrease.
Three factors can affect population size:
Number of births
Number of deaths
The moving of individuals.
Immigration
Moving into an area.
Emigration
Moving out of an area.
Exponential Growth
This occurs when the individuals in a population reproduce at a constant rate.
Logistic Growth
Follows an S shape.
Carrying Capacity
The largest number of individuals that a given environment can hold.
Limiting Factors
Factors that cause population growth to decrease.
Density-dependent
It depends on the population size.
Competition
Competing for resources.
Predation
Predator-Prey relationship.
Parasitism
Parasite attacking the host.
Disease
Takes an organism out of homeostasis.
Density-independent
It does not depend on population size.
Demography
The study of human populations.
What do birth rates, death rates, and the age structure of the population help to predict?
Why some countries have high growth rates while others do not.
Demographic Transition
A dramatic change in birth and death rates.
What are the current projections for 2050 population?
9 billion people
How have human activities affected the biosphere?
Mass extinctions
Agriculture
Growing organisms for food or other resources.
What did agriculture lead to?
Government, laws, and writing.
Monoculture
Large fields planted with a single variate year after year.
Green Revolution
Using resources that greatly increased the world’ s food supply.
What helped pests grow?
Increased food supply.
