Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
21 Cards in this Set
- Front
- Back
|
Population
|
all the individuals of a species that live together in one place at a time
|
|
|
Population size
|
the number of indivuduals in a population
|
|
|
population density
|
the number of indivudials that live in a given area
|
|
|
disperation
|
the way the individuals of the population are arranged in space
|
|
|
three types of dispersion
|
random, even, and clumped
|
|
|
population model
|
a hypothetical population that attempts to exhibit the key characteristics of a real population
|
|
|
exponential growth curve
|
is a curve in which the rate of population grown stays the same, as a result the population size increases steadily
|
|
|
density-dependent factors
|
limited resources amount of water, food
|
|
|
carrying capaity
|
the population size an environment cans sustain
|
|
|
logistic model
|
a population model in which exponential grown is limited by density dependent factors
|
|
|
r-strategists
|
species that adapt and grow rapidly in changing environment, bacteria, mosquitos, cockroaches
|
|
|
K-strategists
|
Organsims that grow slowly and have small populations sizes such as whales
|
|
|
density imdependent factors
|
growth of speies limited by environmental conditions
ex. weather and climate Ex mosquitos pop. increase in summer due to warm weather, decrease during winter |
|
|
Hardy-
weinberg principle |
frequencies of alleles in a population do not change unless evolutionary foreces act on the population
|
|
|
gene flow
|
the movement of alleles into or out of a population
|
|
|
nonrandom mating
|
mating with others that live nearby or of same phenotype
(mating with relatives, inbreeding |
|
|
genetic drift
|
change in an allel's frequency (occurs in small populations/changed by chance event fire, landslide
Cheetas |
|
|
polygenic
|
a trait that is influenced by several genes( human height/skin color
|
|
|
normal distribution
|
hill shaped curve on graph
alleles average value |
|
|
directional selection
|
the frequency of a particular trait moves in one direction in a range.(like pestsicide resistance in insects change of the average value of a population
|
|
|
stabilizing selection
|
distribution becomes narrower
Increases of the number of average individuals |
