Carbon, an important element for life, keeps cycling between the spheres of the Earth. Carbon dioxide in the is absorbed by the oceans and is used by aquatic organisms for biological processes. But aquatic organisms return some of it back through
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In trying to determine whether dna or protein is the genetic material, hershey and chase made use of which of the following facts? a) dna contains sulfur, whereas protein does not. b) dna contains phosphorus, whereas protein does not. c) dna contains nitrogen, whereas protein does not. d) dna contains purines, whereas protein includes pyrimidines.