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Describe the relationship and movement between temperature and density in a convection cell. make sure you identify the direction of travel

Which of the following describes the difference in stimuli required to detect a difference between the stimuli? a. just noticeableb. signal detectionc. subliminald. top down

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.