What Are The Viruses And Bacteria?

A virus is a microscopic particle that infects the cells of a biological organism. At the most basic level, viruses consist of genetic material (DNA or RNA) contained within a protective protein shell called a capsid. A complete virus particle, known as a virion, is little more than a gene transporter, consisting of nucleic acid surrounded by capsid.

Most virologists consider viruses non-living, as they do not meet all the criteria of the generally accepted definition of life. Thus, viruses infect a wide variety of organic cells to live and reproduce. They are only several nanometers in size and are not visible under ordinary microscopes.

Bacteria are a major group of living organisms. Bacteria are the most abundant of all organisms. They are present in soil, water, and as symbionts of other organisms. Many pathogens are bacteria. Bacteria are visible under ordinary microscope. All bacteria reproduce asexually resulting in the production of two identical clone daughter cells. A virus that infects bacteria is known as a bacteriophage, often shortened to phage.