What is Biology?
The study of living organisms, divided into many specialized fields that cover their morphology, physiology, anatomy, behaviour, origin, and distribution.
Deoxyribonucleic acid, is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms and some viruses. It is made of repeated blocks (polymers) called nucleotides, which together form the shape of a double helix. Each nucleotide has a nitrogenous base, a sugar, and one or more phosphate groups. The nitrogenous base is the changing element. It can be adenine, cytosine, guanine or thymine. The bases are either purines or pyrimidines. The purine bases are adenine and guanine and the pyrimidines are cytosine and thymine. The sugar is deoxyribose.