Virus uses the host cells ribosomes to translate the viral genes in the RNA

Virus uses the host cells ribosomes to translate the

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Virus uses the host cell’s ribosomes to translate the viral genes (in the RNA segments) into viral proteins; [1] (c) The RNA segments containing genes PB2, PB1 and PA code for the RNA polymerases shown in Fig 3.1. Explain why such RNA segments are needed by the virus. 1. The RNA-dependent RNA polymerases required by the virus are not present in the host cell; 2. These polymerases are required for the replication of negative-sense viral RNA genome; 3. And transcribe negative-sense viral RNA genome into mRNA, which is then translated to viral proteins; @ 1m [2] (d) Tamiflu (Oseltamivir) is an antiviral drug that is used in the treatment of influenza. It acts as an inhibitor of the neuraminidase on the influenza virus. Explain how inhibiting neuraminidase can prevent influenza. 1. It cannot cleave the sialic acid residues of the receptors on the host cell surface membrane that still bind the mature viruses; 2. New viruses cannot bud off successfully from the infected cells to infect other cells; 3. Viruses also cannot break down the mucoprotein and penetrate mucus layer of the host cell; @ 1m [2] [Total: 8]
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