Chapter 5-6 Flashcards
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.
Fossil Fuels
Coal, OIl, and Natual Gas
Renewable Resource
Can get it back within a lifetime.
Nonrenewable Resource
Cannot get it back in a lifetime.
Sustainable Development
A way of using natural resources without depleting them and not causing long-term environmental harm.
Erosion
Moc=ving soil sediments.
Weathering
Break down of rocks or minerals in the soil.
Desertification
Turning a productive area into a not productive area.
Deforestation
Loss of a forest.
Aquaculture
Raising aquatic animals for food.
Smog
A mixture of chemicals that makes a gray-brown haze in the atmosphere.
Pollutant
Harmful material.
Wetland
Area of land that is wet.
What do wetlands do?
Provide habitat for many species, filter water, and helps control water volume.
Biodiversity
Amount of species in an area.
Extinction
Species disappears from all or part of its range.
Endangered
Population size declines so much it could become extinct.
Biological Magnification
Concentrations of a harmful substance increase in organisms at higher trophic levels.
Example of Biological Magnification
DDT
Invasive Species
New species in an area that reproduce rapidly.
Example of an Invasive Species
Asian Beetles
Conservation
used to describe the wise management of natural resources
Ozone Layer
A layer of Ozone in the atmosphere.
What does the ozone layer do?
Absorbs UV radiation
Global Warming
Increase in the average temperature of the biosphere.
What is the difference between greenhouse effect and global warming
The greenhouse is naturally occurring while Global Warming is caused by humans.
Species
A group of organisms that can reproduce.
Population
A group of species in a given area at a given time.
Biosphere
Where all life is found.
