Is a bacteriophage living or non living entity?

A group of bacteriophages injecting their DNA into a bacterium. Courtesy Image from Eye of Science / Science Source 
Phages like any other viruses possess that complex form of the life cycle that makes them be considered non-living although they still have other characteristics of a living entity. Phages and other viruses are not considered living organisms because they can't carry out biological processes without the help and cellular machinery of another organism. They are complicated assemblies of molecules, including proteins, nucleic acids, lipids, and carbohydrates, but on their own, they can do nothing until they enter a living cell ( bacterial cell in case of phage). Without cells, viruses would not be able to multiply. that's why they are termed non-living things.

List of characteristics of bacteriophage as a living thing and non-living thing

Living characteristics of bacteriophages

Non-living characteristics of Bacteriophages

  • It is capable of multiplying inside a host cell (bacteria)
  • It is an obligatory intracellular parasite.

  • It cannot multiply extracellularly, i.e. Outside the cell.
  • It is capable of infecting another cell (bacteria).
  • Metabolic activity is absent.
  • It possesses nucleic acid (either DNA or RNA), proteins (Capsid), and Enzymes for replication
  • Protoplasm is absent.
  • It has the ability to mutate.
  • Crystallization of viruses is possible.

Viruses are the most primitive cellular and non-cytoplasmic infectious agents. Russian botanist D.J. Iwanowski (1892) first discovered the virus in an infected tobacco plant. However, M.W. Beijerink (1898) coined the term virus. Then American chemist W.M. Stanley (1935) isolated the pure crystal of Tobacco Mosaic Viruses (TMV) and concluded that viruses are made of nucleoproteins.


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