Virus Morphology Study Documents

Virus Morphology The morphology of sizes viruses is very todiverse in shape andBased type.onViruses have different shapes and according their classification. their shape, viruses areandclassified into 4, namely filamentous, isometric/icosahedral, enveloped, head and tail. Viruses that are included in the filamentous group are generally viruses that attack plants such as TMV (Tobacco Mosaic Virus). Isometric viruses are viruses viruses and that adenoviruses. have a roughlyEnveloped round shape which include polio viruses, herpes viruses are viruses that have a membrane surrounding the capsid, which include the HIV virus,of influenza virus and SARS-CoV-2 virus. The head and tail virus group is a type virus whose head isgroup. similarThis to the icosahedral type and the tail is similar to the filamentous virus type of virus usually infects bacteria known as bacteriophages. Filamentous/fibrous viruses arereported identifiedby through viruses that attack namely plants. This identification was first two American scientists, Takahashi and Rawlins, in 1933.disease Observations were made on tobacco plantwhen sap objects infected with mosaic which showed double refraction illuminated by oriented polarizedlike light.logsThese indications statestream. that theThis sap contains stem -like particles flowing in a water phenomenon was later called the tobacco mosaic virus. The icosahedral shape (icosahedron) was viruses first reported by Williams and Smith in(TIV), 1958. They used one of the isometric large, Tipula Iridescent Virus one of the groups with distinctive optical properties. TIV attacks the larvae of the flying crane fly, Tipula paludosa and several other insect species. The size of the virustheis "double-shadowing" around 130 nm and itsmethod. shape isTheobserved by anmodel electronis microscope using icosahedral described and estimated from two light sources whose sources arepoints separated at 60 azimuth and oriented so that the top of the hexagonal contour directly tofour-sided each lightandsource. Thisand phenomenon produces two images, theblunt first image is pointed the second is five-sided with a tip. this phenomenon indicates with considerable confidence that the TIV particles are icosahedronshaped. The shapelittle of the virus particle andthe the disease presencetransmitted or absence byof atheviralvirus envelope provide information about after infection. Bacteriophages that infect Escherichia coli bacteria have a tail structure that the virus uses to attack host cells and a head structure that contains DNA genetic material. Adenovirus, ainnon-enveloped virus that attacks animals and causes respiratory disease humans. Adenoviruses use glycoproteins shaped like spikes protruding from the capsomeres to attack host cells. Apart fromareadenovirus, viruses that arevirus included inhepatitis the sameAclassification as adenovirus papilloma virus, polio and virus. Nonenveloped viruses are known to be more resistant to changes in temperature, pH and ofsome disinfectants.rather fragility the virus envelope. than enveloped viruses. This is due to the Enveloped viruses such as HIV consist of envelope nucleic acidandandsimilar capsid proteins. proteins surrounded by a phospholipid bilayer Glycoproteins embedded in the protein coat areofused to attackviruses or infect host cells. Apart from the HIV virus, other types enveloped include chickenpox, influenza,2).mumps and SARS-CoV-2 (Severe Acute endemic Respiratory Syndrome Coronavirus The SARS-CoV-2 virus which is currently is a class of enveloped viruses from the corona virus family. This virus has a CoVs genome, namely aviruses. single strand of positiveproteins RNA (+ssRNA) which is larger in size than other RNA Nucleocapsid form the capsid outside the genome. The genome is protected or surrounded by a sheath made from the unity of 3 protein structures, namely membrane proteins, spike or needleshaped proteins and protein coats.