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18 Cards in this Set

  • Front
  • Back
These life forms used organic compounds from their environment as sources of energy
heterotropic hypothesis
Life on Earth was probably assissted by life from outer space.
Extra-terrestrial hypothesis
Life began near deep sea vents and the first organisims made their own food from hydrogen sulfide.
Chemoautorophic hypothesis.
Group of organisisms that share similar characteristics and breed with one another.
The process that generates new species
Occurs when indiviuals within a population become spearated geographically from each other for long periods of time.
Allopatric speciation
New species develop without geographical separation
Sympatric speciation
The dissapearance of an entire species
THe extinction of a population from a particular location but not from the entire planet.
found in one or very few locations
endemic species
autotrophs convert light energy from the sun into chemical energy through this process
a light absorbing pigment and the pigment that makes plants green.
Oxygen level below 2-3 mg/L
no oxygen
Energy moves throguh a community as organisms feed on one antoher.
Food chain/web
A simplified, linear representation of energy flow.
food chain
more complex and realistic and shows a varitey of possible flow paths.
food web
position in the feeding hiearchy.
trophic level