Nucleic Acids

Nucleic acids are present in all living organisms, whether plants, animals or viruses. They are generally associated with proteins to form nucleoproteins. There are two types of nucleic acids, deoxyribose nucleic acid (DNA) and ribose nucleic acid (RNA). DNA is found predominantly in the nucleus, while RNA is predominant in the cytoplasm. DNA is the genetic material of most organisms, including many viruses. some viruses, however, have RNA as their genetic material.

Deoxyribose Nucleic Acid (DNA)

DNA is present in the cells of all plants, animals, prokaryotes and in a number of viruses. In eukaryotes it is combined with proteins to form nucleoproteins. In prokaryotes the genetic material consists of a single giant molecule of DNA about 1,000 microns in lengths, without any associated proteins. DNA is present mainly in the chromosomes. It has also been reported in cytoplasmic organelles like mitochondria and chloroplasts. The DNA of all plants and animals and many viruses is double stranded. In some viruses the genetic material is RNA. In the tobacco mosaic virus (TMV), A tobacco virus, influenza virus, poliomyelitics virus and the bacterial viruses F2 and R17 the RNA is single stranded. In the reovirus and the wound tumor virus, however, RNA is double stranded. In bacteria and in higher plants and animals both DNA and RNA are present. Viruses usually contain either DNA or RNA. Viruses usually contain either DNA or RNA.