This set of Microbiology Multiple Choice Questions & Answers (MCQs) focuses on “Viruses Containing Single – Stranded RNA”.
1. Polioviruses belong to which of the following groups?
c) foot and mouth disease viruses
Explanation: Polioviruses belong to the enteroviruses because they are found in the intestines and excreted in the feces. They cause mainly intestinal infections and sometimes infections of the respiratory tract; neurological disease may also be produced.
2. Where does polioviruses multiply first?
c) lymph nodes
d) spinal cord
Explanation: Polioviruses multiply in the oropharynx or intestinal mucosa, pass to the lymphatic system and eventually reach the bloodstream.
3. The Sabin vaccine is 70 to 90 percent effective for immunization against poliomyelitis.
Explanation: The Salk virus is 70 to 90 percent effective and is administered in a series of three intramuscular injections.
4. At what pH values are the rhinoviruses destroyed?
Explanation: Rhinoviruses differ from enteroviruses by being destroyed at pH values of less than 5 (such as would occur in the stomach) and by having an optimal growth temperature at 33 degrees C.
5. Complement- fixation is done for laboratory diagnosis of which of the following disease?
Explanation: Laboratory diagnosis of FMD is done by complement-fixation, virus-neutralization, or mouse-inoculation tests.
6. Eastern equine encephalitis is more fatal than western equine encephalitis.
Explanation: Eastern equine encephalitis has a high mortality rate (50 to 70 percent), whereas western equine encephalitis virus infections are seldom fatal (3%).
7. Yellow fever is caused by ____________
Explanation: Yellow fever is caused by flaviviruses that differ from others in causing a disease in which the liver, kidney, and other organs are affected.
8. Which of the following viruses consists of a helical nucleocapsid?
Explanation: Coronaviruses have a helical nucleocapsid and contain single-stranded RNA of the (+) type.
9. Which drug is used to cure influenza caused by type A strains?
Explanation: A synthetic drug, amantadine, can prevent and even help to cure influenza caused by type A strains; it acts by preventing the penetration and uncoating of the virus after it attaches to a host cell.
10. Which of the following is incorrect with respect to Paramyxoviruses?
a) large (125 to 250 nm)
b) core of single-stranded (—) RNA
c) rna is segmented
d) hemagglutinin and neuraminidase activities occur together
Explanation: The paramyxoviruses are larger (125 to 250 nm), the RNA is segmented and only the (—) strand is present, and the hemagglutinin and neuraminidase activities occur together in a single kind of surface glycoprotein (HN).
11. Crimean-Congo hemorrhagic fever is transmitted by _____________
c) biting flies
Explanation: Crimean-Congo hemorrhagic fever occurs in Africa and Asia and is spread by ticks. This disease is caused by Bunyaviruses.
12. What is the shape of the Rhabdoviruses?
c) brick shaped
Explanation: Rhabdoviruses are 70 to 80 by 130 to 240 nm in size and have a characteristic bullet shape. They have a helical nucleocapsid and contain single-stranded RNA of the (—) type.
Sanfoundry Global Education & Learning Series – Microbiology.
To practice all areas of Microbiology, here is complete set of 1000+ Multiple Choice Questions and Answers.