Microbiology Multiple Choice Questions on “Animals and Plants – Classification of Viruses”.
1. How many dsRNA segments are present in the reovirus genome?
A. 1
B. 3
C. 50
D. 10
Answer: D
Clarification: Reoviruses contain both the + and the — strands of dsRNA and its genome consists of 10 dsRNA segments. During uncoating ten mRNA molecules are transcribed from one strand of the dsRNA and pass into the host cell cytoplasm.
2. Enterovirus belongs to which of the following family of viruses?
A. Tymovirus
B. Picornaviridae
C. Reoviridae
D. Closterovirus
Answer: B
Clarification: Enterovirus belongs to the family Picornaviridae and it has a virion size of 28 nm.
3. Rous sarcoma virus consists of RNA as its genetic material.
A. True
B. False
Answer: A
Clarification: Rous sarcoma virus belongs to Retroviridae family, has a virion size of 100-120. It possesses icosahedral symmetry and consists of RNA as its genetic material.
4. Which of the following viruses possess an envelope?
A. Herpesvirus
B. Reovirus
C. Tobacco mosaic virus
D. Papillomavirus
Answer: A
Clarification: Herpesvirus possesses an icosahedral symmetry and contains DNA as its genetic material. Its nucleocapsid is surrounded by an envelope.
5. Which of the following viruses have a complex symmetry?
A. Alphavirus
B. Mobillivirus
C. Orthopoxvirus
D. Parvovirus
Answer: C
Clarification: Orthopoxvirus posseses a complex symmetry and is surrounded by a coat. It consists of DNA as its nucleic acid.
6. The family of Rhabdoviridae possesses dsRNA.
A. True
B. False
Answer: B
Clarification: The family of Rhabdoviridae consists of ssRNA and they are enveloped. An example is vesicular stomatitis.
7. Cowpea virus belongs to which of the following group of viruses?
A. Comovirus
B. Dianthovirus
C. Cucumovirus
D. Carlavirus
Answer: A
Clarification: Cowpea mosaic belongs to the Comovirus group of viruses. They are non-enveloped and possess ssRNA.
8. For the cultivation of viruses the fertile chicken eggs should be incubated for how many day(s)?
A. 1
B. 2-4
C. 5-12
D. 2-7
Answer: C
Clarification: For the cultivation of viruses by embryonated chicken eggs, the fertile chicken eggs should be incubated for 5 to 12 days and then they can be inoculated through the shell aseptically.
9. Which of the following method is used for the production of vaccines against yellow fever?
A. tissue-culture method
B. chick-embryo method
C. through susceptible animals
D. through appropriate media
Answer: B
Clarification: The chick-embryo technique has been used in the production of vaccines against smallpox, yellow fever, influenza, and other diseases and in immunologic tests and other studies whenever large amounts of virus are required.
10. The karyotype of cells formed from continuous cell lines is _______________
A. haploid
B. diploid
C. aneuploid
D. haploid and diploid
Answer: C
Clarification: The karyotype of cells cultured through continuous cell lines is aneuploid i.e., a variable multiple of the haploid chromosome number and not diploid.
.