Structure of a DNA molecule

Question

Elaborate the structure of a DNA molecule?

Answer 1

The molecule of a DNA is double-stranded. The molecule takes the shape of a double helix.
The DNA molecule has two complementary strands oriented in an anti-parallel fashion. All strand is made up of nucleotides. A nucleotide has a base (a purine or pyrimidine), a sugar (between the other two components) called deoxyribose, and a phosphate group. Nucleotides are connected to each other with phosphodiester bonds, creating a sugar-phosphate backbone to each strand.
Base of each nucleotide projects into an interior cavity of helix. Every base is opposite other base: adenine (a purine) is every time paired with the thymine (a pyrimidine), and the guanine (purine) with the cytosine (pyrimidine); this phenomenon is known as complementary base pairing.
Every nucleotide forms hydrogen bonds with its complementary base on another strand. Two hydrogen bonds form among adenine and thymine; three hydrogen bonds form between guanine and cytosine.