RodBrieger520 RodBrieger520
  • 03-04-2014
  • Biology
Answered

During the evolution of life on Earth, the photosynthetic organisms initially responsible for raising atmospheric oxygen concentrations from less than 1 percent to about 20 percent were
(A) cyanobacteria
(B) archaea
(C) diatoms
(D) flowering plants
(E) mosses

Answer :

chaospaulo chaospaulo
  • 03-04-2014
B or A the chapter I learned talked about both
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