DNA consists of two polynucleotide chains, Each chain forms a right-handed spiral with how many bases in one…
DNA consists of two polynucleotide chains, Each chain forms a right-handed spiral with how many bases in one turn of spiral?
4
6
8
10
Solution
Watson and Crick proposed that DNA molecule is in the form of a double helix with two polynucleotide chains coiled around one another in a spiral. This is known as B-DNA or biological DNA. It has 10 nucleotides pairs per turn of the double helix and is right handed with a diameter of \(20 Å\). One complete turn of the double helix is \(34 Å\). The distance between adjacent stacks or nucleotides is \(3.4 Å\). Hence, option (d) is correct.