Question

DNA is the molecule used to store the genetic code of most living organisms on earth. Its structure was famously proposed by Watson and Crick who proposed double helix structure published in the journal Nature, April 25, 1953. For this the Nobel Prize was awarded to Watson, Crick & Wilkins in 1962. (a) (i) (ii) Show the chemical structure of the DNA backbone. What is a 1. the backbone, 2. a nucleoside, 3. a nucleotide 4. a nucleic acid? (b) Using the following diagram identify: (i) (ii) (iii) The dimensions (length of repeat unit and diameter) of the structure. The major groove. The minor groove. What are the two main structural differences between DNA and RNA? (d) (1) (ii) Which of the bases (Adenine, Cytosine, Guanine and Thymine) pair together? Show the H bonding interactions in the base pairing of the nucleoside bases.

Answer 1

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