.

Friday, June 14, 2019

Are Viruses Considered To Be Living Organisms Essay

Are Viruses Considered To Be Living Organisms - Essay ExampleIn 1876, even though the nature of virus was non recognized at the time, yet, it was anticipated that the number of species of virus are greater than that of all other subsisting things put together. Viruses are parasites as they cant nurture themselves and require a horde cell for nutrition, growth and reproduction. All viruses are harmful in fact their capability to operate as winding genes is considered to have inclined the hereditary make-up and development of higher living beings. Indeed their similarity to the genetic material of higher organisms that can move from wiz genetic material to another can be considered to be as evidence of their beginning. Nowadays, many experts consider that viruses have been descended from bacterial plasmids (small package of genes residing on the satellite side of the chromosomes of bacteria and have the ability to transfer from one bacterium to another). Viruses are not similar t o human or bacterial cells. They are niggling creatures that cant be seen with a normal light microscope. Their size is said to be of only one-millionth part of an inch. Viruses may even give bacteria to reproduce themselves the Bacteriophage virus for example requires bacteria for the completion of its life cycle. Once infected, the host cell stops its functioning rather starts serving the viral requirements resulting in the onset of infection to the host (Holzenburg and Bogner, 2002). Viral Structure A virus mainly consists of three parts. 1. Capsid It is a protein coat that meet the nucleic acid to protect it. 2. Nucleic acid It is the basic genetic material either RNA or DNA that grasps all the data for the virus and contrast all(prenominal) virus from another. 3. Envelope It is a lipid membrane that envelops the capsid (protein coat). However, it is not present in all viruses. Those viruses that possess envelop are said to be enveloped viruses while those that lack it a re called naked viruses. Fig1. Characteristic Viral Structure Lytic cycle The lytic cycle which represents the life cycle of virus involves six basic locomote 1. Adsorption as the virus gets attached to the host cell. 2. Entry The attached virus then penetrates the cell by injecting its genetic instructions (RNA or DNA) into the cytol of the host cell. 3. Transcription The injected viral genetic material takes control of the host cells nucleus and starts directing the enzymes of the host. 4. Replication Fragments of new viruses are make using particular enzymes. 5. Assembly The fragments formed are then assembled to form new viruses. 6. Release The novel viruses destroy the host cell and burst turn up to attack new host cells and continue this cycle. Virus Non Living or Living? Viruses are usually kept on the borderline between living and non living beings. Some features of viruses make them considered as living beings while other lead to the development of opinion of considering them as non living. Viruses are regarded as living on the basis of their proposed evolution via natural selection and ability to reproduce themselves. Viruses can be regarded non living as they are acellular and require a host to perform its metabolic and reproductive activities. Viruses are convoluted assemblage of molecules, including nucleic acids, proteins, carbohydrates and lipids, but unable to do anything on their own until they penetrate the host cell. The

No comments:

Post a Comment