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57 Cards in this Set

  • Front
  • Back
change of species overtime
break down molecules and tend to be exergonic
darwin, study of the geographic distribution of life forms on earth.
natural selection
brings about adaptation to the environment adaptive characterisics that enable an organism to survive and reproduce. functional, physical, behavioral.
ability of an organism to survive and reproduce in its immediate enviroment
trait that helps an organism to be more suited to it's environment
ex flippers
comparative anantomy
shows homologous similarities between organisms.
accumulation of small changes in a gene pool over a short period
genetic drift
change in allele frequency of a gene pool due to change (smaller populations)
Hardy Weinberg law
equilibrum of allele frequencies in the gene pool remain constant in a sexually reproducing population if:
Hardy Weinber law is possible if?
- no net mutations
- no gene flow
-no genectic drift
-no selections
assortative mating
when individuals tend to mate with others of the same phenotype
founder effect
where rare alleles occur in higher frequency
bottleneck effect
when a pop. is subject to near extinction and rebounds. genectic similarity
stabilizing selection
when the intermediate is favored over extreme phenotypes
ex birthweight
disruptive selection
when 2 extreme phenotypes are favored
directional selection
when one exteme is favored over other extreme
isolating mechanisms
any structural, functional, or behavioral characteristic that prevents successfull reproduction.
habital isolation
two species occupy different habitats,
ex rain forrest.
temporal isolation
two species in the same location, reproduce at diff. times.
allopatric speciation
geographic isolation of pop. from each other
ex island chains
sympatric speciation
reproductive isolation in areas when there is not geographic isolation
what biologists believe
a- abiotic synthesis produced small organic molecules in atmosphere/vents
b- more complex compounds formed along a shore or at a vent
what biologists believe
c- protocell with a plasma membrane is produced
d- once a protocell contained dna it becomes a true cell
prokaryotic cells date back
3.5 billion
eukaratoic date back
2.2 billion
multicellular organisms date back
1.4 billion
any action that can be observed and described, anatomy and physiology determine what types of behavior are possible.
durable change in behavior brought about by experience
dominance hierarchy
ranking within a group where higher ranking aquire more
marking and defending an area for feeding, mating, broodrearing.
social group living advantages
-more choices in mates
-finding food
social group living disadvantages
-illness/ parasites
- more compition for food
where an organism lives
all organisms of the same species in an area
all populations within an area
a community of a pop. and the abiotic environment
biotic potential
maximun rate of natural increase under ideal conditions
biotic potential depends on:
- usual # of offspring is one
-chances of survical until age of reproduction
-how often individual reproduces
-age at which reproduction starts
survivorship curve type 1
most die of old age

mammals, annual plants
survivorship curve type 2
die at constant rate

birds, rodents
survivorship curve type 3
die early

fish, bugs
when members of the same species try to us limited resources
when one organism(predator) feeds on another (prey)
opportunistic specices
-short life span
-fast maturing
-numerous offspring
-no/little care for offspring
-early repro age
equilibrium species
-long life span
-slow maturing
-few offsping
-lots of care for offspring
-stable environment
both species richness (# of species) and species evenness
community structure
compation can occur between diff. species, or within a species
role of species plays in a community
where an organism lives
competive exclusion princple
no two species can occupy the same niche at the same time.
have a broad range of niches

deer, coyotes
have a narrow range of niches

panda's, spott owls
a change involving a series of species replacements in a community following a disturbance.
intermediate disturbance hypothesis
moderate amount of disturbance at moderate frequencies are required for a high degree of a community deversity.
producers (make own food)