explain why the structure of a dna molecule is often described as a zipper
A molecule of DNA is double-stranded. The molecule has the shape of a double helix, typically right handed (B form DNA). The DNA molecule consists of two complementary strand â¦ s oriented in an antiparallel fashion. Each strand is composed of nucleotides.A nucleotide consists of a base (a purine or pyrimidine), a sugar (between the other two components) named deoxyribose, and a phosphate group. Nucleotides are linked to each other via phosphodiester bonds, forming a sugar-phosphate backbone to each strand.wo hydrogen bonds form between adenine and thymine; three hydrogen bonds form between guanine and cytosine. There are three forms of DNA that differ significantly. The most common, B form, is the structure most people have heard of.