What Is Viruses
Viruses are the smallest known microbes or infectious agents. The simplest viruses consist of a core of nucleic acid surrounded by a protein coat known as a capsid; this nucleic acid-protein complex is referred to as a nucleocapsid. In more complex viruses the nucleocapsid is surrounded by an envelope, which is a membrane-like structure containing carbohydrates,lipids and proteins. Viruses contain either ribonucleic acid
(RNA) or deoxyribonucleic acid (DNA), which are large complex chemicals that contain the viruses’ genetic code and serve as a blueprint for making more viruses.

