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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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DNA model described by Watson and Crick was
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The correct answer is  The DNA molecule consists of two polynucleotide chains or strands that spirally twisted around each other and coiled around a common axis to form a right-handed double-helix. The two strands are antiparallel i.e. they ran in opposite directions so that the 3' end of one chain facing the 5' end of the other. The sugar-phosphate backbones remain on the outside, while the core of the helix contains the purine and pyrimidine bases. Ref-Sathyanarayana 4/e p400