if bacteria divide at the rate they do, why dont they take over the worl
beacuse of the limiting factors- water, food, nutrients, and space
whats is a population
a group of organsims all the same species that interbreed and live in the same place at the same time
what is population growth
the increase in size of the population over time
what is one method of studying population changes
intoduicng organisms to a controlled enviorment with abundent resources and watching how they react
what is required to study larger populations
ratio moniters
what are the two types of life history patterns
slow and rapid
what are 3 characteristics of slow life history
reproduce slowly, few offspring, long gestation period, mature slowly, long lives, maintain population, population size at or near carry capacity
name 3 characteristics of rapid life history
reproduce early and rapidly, many offspring at once, small body size, mature rapidly, short life span, populations increase rapildy, then decline when enviormentqal conditions change and become unsitable for life such as insects or bacteria
what are the three types od dispersal patterns
random, inoform, and clumping
what are examples of the three types of dispersals
flowers/random trees/uniform musgrooms/clumping
what are the 2 limiting fctors of dispersal
1. density dependent
2. density independent
what is population density
refers to the number of individuals in an area
what are some examples of density dependent
disease, competition, predators, parasites, food
what are some examples of density independent
volcanic eruptions, temperature, natural disaters, chemical pesticides. and major habitat destruction
what are the 3 limiting factors of population size
predation, crowding, competiton
what are 4 negative effects on an organism due to crowding
decreased fertility, decreased parental care, aggresion, and descreased resistance to disease
why dont populations of organisms grow indefinatly
limiting factors
what is carrying capacity
the number of organisms of one species that an enviorment can support
if the number of organisms in a population is _______ the enviorments carrying capacity, births _______ deaths and the population ______
under, exceeds, grows
if the number of organisms rises ________ the carrying capacity of the enviorment,_______ will exceed _______
above, deaths, births
the most important factor that determines population growth is the organisms
reproductive pattern
organisms that follow a rapid life history pattern have short life spans, small bodies, and reproduce early
true
what is a limiting factor that has an increasing effect as population size increases is
competition
what symptoms can cause a decrease in a population
aggression, decrease in parental care, decreased fertiltiy, decreased resistance to disease, overcrowding
what is life expectancy
how long an average person is expected to live
what is fertility rate
the rate at which fertility occurs
what is migration
instinctive seasonal movements of animals from place to place
what is immagration
movements of individials
what is emigration
movement of a population
