Viruses: Complex Molecules Or Simple Life Forms? :: essays research papers

Viruses Complex Molecules or Simple Life Forms?Viruses have been defined as "entities whose genomes atomic number 18 elements ofnucleic sulphurous that replicate inside living cells using the cellular syntheticmachinery, and crusade the synthesis of specialised elements that can transfer thegenome to other cells." They are stationaryand are unable to grow. Because ofall these factors, it is debatable whether viruses are the most complex ofmolecules or the simplest life skeletal systems. While the definition of living organismsmust be adapted, the majority of evidence leads to the classification of virusesas living organisms.Viruses are compose of a nucleic acid core, a protein mirid, andoccasionally a membraneous envelope. The nucleic acid core is composed ofeither DNA or in the case of retroviruses, RNA, but never both. In retroviruses,the RNA gets transcribed to DNA bye the enzyme reverse transcriptase. Theprotein capsid is a protein layer that wraps around the virus . There are four staple fiber shapes of viruses. The tobacco mosiac, adenovirus, influenza virus, andt-even bacteriophage are each examples of a unlike virus structure. Eachindividual protein subunit composing the capsid is a capsomere.The tobacco mosiac virus has a helical capsoid and is rod shaped. Theadenovirus is polyhedral and has a protein spike at each vertex. The influenzavirus is made of a flexible, helecal capsid. It has an outer membranousenevelope that is covered with glycoprotein spikes. The T-even bacteriophageconsists of a polyhedral result and a tail. The tail is used to inject DNA into abacteria while the head stores the DNA.Basic life is defined as the simplest form capable of displaying themost essential attributes of a living thing. This makes the only echt criterionfor life the ability to replicate. Only systems containing nucleic acids arecapable of this phenomenon. With this reasoning, a better definition is theunit element of a continuous argument with an individual evolutionary history.Because of viruses inability to survive when not in a host, they must haveevolved from other forms of life. The origin of viruses is an easy thing tohypothecate about so many hypothesese have been made.One such speculation is that viruses were once complete living parasites.Over time they have woolly all other cellular components. This is backed up bythe belief that all cells degenerate over time.Some people think on very similar lines that viruses arerepresentatives of an early "nearly living" format of life. This goes along withthe first hypothesis in that it accounts for a loss of components. everycreatures that become parasitic can be seen losing their obsolete functions and