Virology Questions and Answers – Process of Viral Infection – 2

This set of Virology Interview Questions and Answers for Experienced people focuses on “Process of Viral Infection – 2”.

1. Replicases are used in _______________
a) translation
b) replication
c) transcription
d) post-translation
View Answer

Answer: b
Explanation: Replicases are the enzymes used in the replication of the genome. Replicases are usually the Polymerases used in the replication of the RNA genome. They are referred to as replicase to differentiate polymerases involved in transcription.

2. The error rate during RNA replication is approximately _____________
a) 10-5 to 10-7
b) 10-7 to 10-9
c) 10-3 to 10-5
d) 10-1 to 10-3
View Answer

Answer: c
Explanation: The error rate during RNA virus replication is estimated to be approximately 10-3 to 10-5 per base per genome replication event. This places a limit on the maximum size of an RNA-based genome since as the size of the genome increases the probability of it containing a mutation will also increase.

3. Which of the following component in genetic control encodes a repressor protein of 236 amino acids?
a) cI
b) cII
c) cIII
d) N
View Answer

Answer: a
Explanation: The component involved in encoding a repressor protein of 236 amino acids is cI. It is transcribed from its promoter and encodes repressor protein which binds to OR and prevents the transcription of cro protein.
advertisement
advertisement

4. An antiterminator protein is encoded by ____________
a) cro
b) N
c) cII
d) R
View Answer

Answer: b
Explanation: N is a component in genetic control that encodes an antiterminator protein and it acts as an alternative rho (ρ) factor for host-cell RNA polymerase, modifying its activity and permitting extensive transcription from PL and PR.

5. Which of the following RNA Polymerase is insensitive to α-amanitin?
a) Pol II
b) Pol IV
c) Pol III
d) Pol I
View Answer

Answer: d
Explanation: RNA polymerase I is unaffected or insensitive to α-amanitin. It transcribes ribosomal RNAs. Whereas Pol II is highly sensitive and Pol III is moderately sensitive to α-amanitin.
Note: Join free Sanfoundry classes at Telegram or Youtube

6. Which of the following is programmed cell death?
a) Necrosis
b) Toxicity
c) Apoptosis
d) Infection
View Answer

Answer: c
Explanation: Apoptosis is also known as programmed cell death. It is a critical mechanism in tissue remodeling during development and in cell killing by the immune system. It is a tightly regulated process.

7. The gene for Interferon-β is located on _______________
a) chromosome 9
b) chromosome 4
c) chromosome 12
d) chromosome 10
View Answer

Answer: a
Explanation: The single gene for Interferon-β is located on human chromosome 9. The mature protein contains 145 amino acids and is glycosylated with approximately 30% homology to other interferons. It is predominantly synthesized by fibroblasts.
advertisement

8. The active form of the reverse transcriptase enzyme is a ________________
a) tetramer
b) trimer
c) dimer
d) monomer
View Answer

Answer: c
Explanation: The active form of the reverse transcriptase (RT) enzyme is a dimer. It is formed of two related polypeptides i.e. a heterodimer. RT from avian retrovirus is composed of alpha and beta subunits.

9. Which of the following surface molecule is used by the Coxsackie B virus as a receptor?
a) IgA
b) MHC I
c) CAR
d) DC-SIGN
View Answer

Answer: c
Explanation: Coxsackie adenovirus receptor (CAR) is a surface molecule that is used by the Coxsackie B virus as a receptor. It is a unique protein of unknown function and it is also used by Adenovirus.
advertisement

10. The gene for Interferon-gamma is located on chromosome 18.
a) True
b) False
View Answer

Answer: b
Explanation: The single gene for Interferon-gamma (γ) is located on human chromosome 12. The mature protein contains 146 amino acids and is glycosylated and has very low sequence homology to other interferons.

11. Interferon-α is synthesized by lymphocytes.
a) True
b) False
View Answer

Answer: a
Explanation: Interferon-alpha (α) is synthesized predominantly by lymphocytes and all the genes encoding interferon-alpha are located on chromosome 9 and there are about 15 molecular species of interferon-α.

Sanfoundry Global Education & Learning Series – Virology.

To practice all areas of Virology for Interviews, here is complete set of 1000+ Multiple Choice Questions and Answers.

If you find a mistake in question / option / answer, kindly take a screenshot and email to [email protected]

advertisement
advertisement
Subscribe to our Newsletters (Subject-wise). Participate in the Sanfoundry Certification contest to get free Certificate of Merit. Join our social networks below and stay updated with latest contests, videos, internships and jobs!

Youtube | Telegram | LinkedIn | Instagram | Facebook | Twitter | Pinterest
Manish Bhojasia - Founder & CTO at Sanfoundry
Manish Bhojasia, a technology veteran with 20+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He lives in Bangalore, and focuses on development of Linux Kernel, SAN Technologies, Advanced C, Data Structures & Alogrithms. Stay connected with him at LinkedIn.

Subscribe to his free Masterclasses at Youtube & discussions at Telegram SanfoundryClasses.