ecology quiz 3 Flashcards
(13 cards)
what is population density
number of individuals per unit area
example
people per square mile
population growth
affected by birth and death rates,people entering or exiting population
immigration
organisms entering
emgration
organisms leaving
exponential growth in population
found only in population with ideal conditions and unlimited resources
not realistic
logistic growth
a realistic model as resources become less available growth slows or stops following a period of exponential growth
what is the carrying capacity
When the growth rate stops and the population will maintain at the number that area can hold
limiting factor
causes population growth to decrease theses become limiting only when population density reaches a certain level
parasitism or decrease
similar to predation but the parasite depend on the host for survival
density independent factors
there affect all populations regardless of population size example natural disasters,seasonal cycles
populations usually show a dramatic crack but may recover
what is bioaccumulation
when exposed to a chemical that chemical increased in your body
biomagnification
when a chemical is in a population as you go up the food chain the amount of chemical increases
overshoot
when the population goes over its max limit
