Busy. Please wait.
Log in with Clever

show password
Forgot Password?

Don't have an account?  Sign up 
Sign up using Clever

Username is available taken
show password

Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
Your email address is only used to allow you to reset your password. See our Privacy Policy and Terms of Service.

Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
Didn't know it?
click below
Knew it?
click below
Don't Know
Remaining cards (0)
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

Population Ecology

Population and how they interact with their environment

Population All the individuals of a species that live together in an area
Demography The statistical study of populations, allows predictions to be made about how a population will change
Three Key Features of Populations 1. Size 2. Density 3. Dispersion
Size Number of individuals in an area
Growth Rate (birth rate + Immigration) - (death rate + emigration) =Rate of population growth How many individuals are born and move into an area vs how many die and move out of the area
Density measure of population per unit area or unit volume
Population Density # of individuals / unit of space
Immigration movement of individuals into a population
Emigration movement of individuals out of a population
Density- dependent factors Biotic factors in the environment that have an increasing effect as population size increases (disease, competition, parasites)
Density- independent factors Aboiotic factors in the environment that affect populations regardless of their density (temperature, weather) A cold snowy winter can decrease birth rates and increase death rates in the spring for deer
Dispersion: spacing of organisms Clumped (aggregated), Uniform, Random
Population density Number of individuals in a given area or volume; count all individuals in a population, estimate by sampling, mark-recapture method
Idealizing models describe two kinds of population growth 1. Exponential Growth 2. Logistic Growth
Exponential Growth A pattern of slow then rapid growth of a population. Growth curve resembles a J.
Logistic Growth A pattern of slow then rapid growth finish in a stable population at carrying capacity growth curve resembles an S.
Carrying Capacity (K) -The maximum population size that can be supported by the available resources. -There can only be as many organisms as the environmental resources can support
Declining birth rate or increasing death rate are caused by -Limited food supply -The buildup toxic wastes -Increased disease -Predation
R Strategists -Short life span -Small body size -Reproduce quickly -Have many young -Little parental care
K Strategists -Longest life span -Large body size -Reproduce slowly -Have few young -Provides parental care
Age Distribution -Distribution of males and females in each age group of population -Used to predict future population growth
Species diversity The more species and number of that species that occupy a habitat the more diverse the community is
Ecological diversity The more diverse an ecosystem is the more stable it is and the more it has to offer in resources
Genetic diversity The more diverse the genetics of a species the less likely it is to collapse in the face of hardship
Habitat loss -The single most common cause of species extinction -Reduces biodiversity
Reasons for habitat loss -Farming -Logging -Urbanization
Ecological service -Bees pollinate flowers -Roots hold soil -Predators prevent overgrazing
Economic benefit -Honey, fruit and other crops are valuable and depend on diversity of pollinators -Plants can be used for medical needs
Human population growth - J curves growth -Rate: 1.3% yearly -Growing rate is 80 million yearly
Mutualism Both species benefit
Parasitism One organisms benefits at the expense of another
Commensalism One species benefits while the other is not affected
Climax community A community goes through succession, then when it is stable at the very end it is the climax
Climate change The recent rise in earths surface temperatures
Created by: kieren1
Popular Biology sets




Use these flashcards to help memorize information. Look at the large card and try to recall what is on the other side. Then click the card to flip it. If you knew the answer, click the green Know box. Otherwise, click the red Don't know box.

When you've placed seven or more cards in the Don't know box, click "retry" to try those cards again.

If you've accidentally put the card in the wrong box, just click on the card to take it out of the box.

You can also use your keyboard to move the cards as follows:

If you are logged in to your account, this website will remember which cards you know and don't know so that they are in the same box the next time you log in.

When you need a break, try one of the other activities listed below the flashcards like Matching, Snowman, or Hungry Bug. Although it may feel like you're playing a game, your brain is still making more connections with the information to help you out.

To see how well you know the information, try the Quiz or Test activity.

Pass complete!
"Know" box contains:
Time elapsed:
restart all cards