JEE MAIN - Chemistry (2003 - No. 27)
The reason for double helical structure of $$DNA$$ is operation of
dipole-dipole interaction
hydrogen bonding
electrostatic attractions
van der Waals' forces
Shpjegimi
$$DNA$$ consists of two polynucleotide chains, each chain forms a right handed spiral with ten bases in one turn of the spiral. The two chains coil to double helix and run in opposite direction held together by hydrogen bonding.