November 30, 2024 by Vijay Wardhan 1. Longest known virus is: TMV _ _ 174 T1 phase Citrus tristeza Explanation:The Tobacco Mosaic Virus (TMV) is one of the longest known viruses. It has a rod-shaped structure and was one of the first viruses to be studied in detail. 2. In which of the following, RNA is the genetic material? Influenza virus TMV All of the above Poliomyelitis virus Explanation:TMV, Influenza virus, and Poliomyelitis virus all have RNA as their genetic material. These RNA viruses rely on RNA-dependent mechanisms for replication within host cells. 3. An infectious agent associated with certain mammalian degenerative disease that is composed solely of protein, is known as: virus prion virion mycoplasma Explanation:Prions are infectious agents composed solely of proteins. They are responsible for several neurodegenerative diseases in mammals, including Creutzfeldt-Jakob disease and mad cow disease. 4. TMV was isolated in crystalline form by: E.C. Stakmanz W.M. Stanley D. Ivanowski K.M. Smith Explanation:W.M. Stanley was the first to crystallize the Tobacco Mosaic Virus (TMV), demonstrating that viruses could be purified and studied in a crystalline form. His work earned him the Nobel Prize in Chemistry. 5. Infective nature of Tobacco mosaic disease was discovered by: Ivanowski Mayer Green Bawden Explanation:Adolf Mayer discovered the infectious nature of Tobacco Mosaic Disease. He demonstrated that the disease could be transmitted from plant to plant, laying the groundwork for the study of plant viruses. 6. Group of viruses, which attack members of Myxophyceae are termed as: cyanophages bacteriophages phages only mosaic virus Explanation:Cyanophages are viruses that specifically infect cyanobacteria (Myxophyceae). These viruses play a role in regulating cyanobacterial populations in aquatic ecosystems. 7. Which of the following is true for viruses? Behave as if they are plants Multiply only in host cells Occur only inside bacteria Are made-up of proteins only Explanation:Viruses can only multiply within the living cells of a host organism. They lack the cellular machinery necessary for independent replication and rely on the host’s cellular processes to reproduce. 8. The genetic material of poxvirus is: double stranded RNA single stranded RNA circular DNA single stranded DNA Explanation:Poxviruses have double-stranded DNA as their genetic material. This allows them to replicate within the cytoplasm of the host cell, independent of the host’s nuclear machinery. 9. In which of the following, RNA is double stranded: wound tumour virus reovirus none of the above both (a) and (b) Explanation:Both reovirus and wound tumour virus have double-stranded RNA as their genetic material. This is a unique characteristic among viruses, as most RNA viruses have single-stranded RNA. 10. Which of the following disease is caused by virus? Typhoid T.B. Polio Diphtheria Explanation:Polio is caused by the poliovirus, which infects the nervous system and can lead to paralysis. The disease has been largely eradicated through widespread vaccination efforts. Loading …
