Free Viruses MCQs with Answers
247 Viruses MCQs from Biology, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Viruses are acellular infectious particles made of genetic material enclosed by a protein capsid, sometimes with a lipid envelope. Their replication depends on a host cell and may follow lytic or lysogenic cycles, so viral structure and reproduction differ fundamentally from those of cellular organisms such as bacteria.
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247 questions · page 10 of 13
- A. For naked virions, the surface capsid proteins are responsible for binding to a specific cell receptor.
- B. For enveloped viruses, the spikes are responsible for binding to a specific cell receptor.
- C. cell lacking a receptor for a specific virus is not infected by that virus.
- D. All of the above.
Explanation: .The surface of capsid protein is responsible for binding to a specific cell receptor in naked virions.
Correct answer: All of the above.- A. TMV
- B. T4 Phage
- C. Poxvirus
- D. Herpes virus
Explanation: Tobacco mosaic virus (TMV) is a well-studied plant virus that belongs to the Tobamovirus genus.
Correct answer: TMV- A. Induction
- B. Penetration
- C. Lytic
- D. Lysogenic
Explanation: The process in which a phage (bacteriophage) integrates its genetic material into the host bacterium's chromosome and becomes a part of it…
Correct answer: Lysogenic- A. Lysogenic cycle
- B. Lytic cycle
- C. Both
- D. None
Explanation: Maturation is when the nucleic material of the bacteriophage has been replicated and now new bacteriophages are being assembled for…
Correct answer: Lytic cycle- A. T-phages
- B. P-phages
- C. Both
- D. None
Explanation: Bacteriophages, or simply phages, are viruses that infect and replicate within bacteria.
Correct answer: T-phages- A. self-replication in host cell
- B. duplication
- C. self-duplication
- D. multiplicate in host cell
Explanation: Bacteriophages are used to insert genes inside host cells as they are small enough to enter and replicate inside the host cells as they…
Correct answer: multiplicate in host cell- A. DNA enveloped virus
- B. RNA enveloped virus
- C. DNA virus
- D. RNA non-enveloped virus
Explanation: Like other OPXVs, VARV and MPXV produce large brick-shaped particles that are approximately 140-260 nm in diameter and 220-450 nm long…
Correct answer: DNA enveloped virus- A. Vector
- B. Capsid
- C. Plasmid
- D. Genome
Explanation: Option B is correct since the 'capsid' is the protein shell that encloses the nucleic acid.
Correct answer: Capsid- A. Animals
- B. Bacteria
- C. Plants
- D. All of the above
Explanation: Viruses cannot replicate on their own, but rather depend on their host cell's protein synthesis pathways to reproduce.
Correct answer: All of the above- A. Tail
- B. Sheath
- C. Collar
- D. Head
Explanation: Option D is correct since the double-stranded DNA molecule is present within the head. The upper hexagonal-shaped part is the head.
Correct answer: Head- A. AIDS
- B. Malaria
- C. Influenza
- D. Chickenpox
- E. Rabies
Explanation: Malaria is not a viral disease and is caused by protozoa plasmodium. All other options are viral infections that include: AIDS caused by…
Correct answer: Malaria- A. Rough endoplasmic reticulum
- B. Golgi complex
- C. Nuclear envelope
- D. All of these options are correct
Explanation: Viruses can bud at every stage in the ER-Golgi-cell membrane pathway.
Correct answer: All of these options are correct- A. Fungus
- B. Prokaryote
- C. Living organism
- D. Obligate intracellular parasite
Explanation: Bacteriophages are actually obligate intracellular viruses. This means that they can only replicate and complete their life cycle by…
Correct answer: Obligate intracellular parasite- A. It is an individual unit of the capsid
- B. It is a viral protein for replication
- C. It is a unit of nucleic acid in viruses
- D. All of the above
Explanation: Correct option: A Capsomeres are subunits of capsids.
Correct answer: It is an individual unit of the capsid- A. icosahedral virus
- B. naked virus
- C. enveloped virus
- D. bilayer virus
Explanation: Correct Option:B This option is correct because naked viruses are those viruses which lack a nuclear envelope
Correct answer: naked virus- A. reproduce independently
- B. contain DNA
- C. contain RNA
- D. extracellular
Explanation: Correct Option:AVirions cannot reproduce independently.
Correct answer: reproduce independently- A. Rod
- B. Spherical
- C. Tadpole
- D. Helical
Explanation: A typical bacteriophage is like a tadpole shaped consists of a head, enclosing the nucleic acid, a base plate and a tail having tail…
Correct answer: Tadpole- A. 150 nm
- B. 100 nm
- C. 200 nm
- D. 250 nm
Explanation: The diameter of retroviruses typically ranges from approximately 80 to 120 nanometers (nm).
Correct answer: 100 nm- A. Viruses have been successfully grown in pure culture test tubes
- B. All viruses are obligate intracellular parasites
- C. All viruses have either DNA or RNA as their genetic material
- D. Viruses probably arose from small fragments of cellular chromosomes
Explanation: Among the following options, option A is incorrect as viruses cannot be grown in pure culture in the laboratory as they are acellular and…
Correct answer: Viruses have been successfully grown in pure culture test tubes- A. Pores develop
- B. Glycocalyx layer is formed
- C. Membrane is resynthesized
- D. Viral proteins are acquired
Explanation: During attachment and penetration, the virus attaches itself to a host cell and injects its genetic material into it.
Correct answer: Viral proteins are acquired