All Free Biology MCQs with Answers

• 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. None of the above

Explanation: The virus attachment protein is the viral protein that facilitates the docking of the virus to the plasma membrane of the host cell, the…

• A. Virophage
• B. Lysophage
• C. Bacteriophage
• D. None of these

Explanation: A bacteriophage is a type of virus that infects bacteria. In fact, the word "bacteriophage" literally means "bacteria eater," because…

• A. Satellite virus
• B. HAV
• C. HCV
• D. HIV

Explanation: Satellite viruses are a polyphyletic group of viruses encoding structural components of their virions, but incapable of completing the…

• A. Adenovirus
• B. Herpes virus
• C. Poliovirus
• D. None of these

Explanation: The correct option is B as out of all the above-mentioned viruses, only herpes virus is an enveloped virus as it has a lipid envelope…

• A. 1
• B. 20
• C. 3
• D. 4

Explanation: In icosahedral viruses, the capsomeres are arranged in equilateral triangles.

• A. Picornavirus
• B. Parvoviruses
• C. Herpes virus
• D. Rotavirus

Explanation: Option B is correct since parvoviruses are the smallest icosahedral particles about 18-26 nm in diameter.

• A. 100 to 160 nm
• B. 20 to 250 nm
• C. 100 nm to 360 nm
• D. Always below than 100 nm

Explanation: The average diameter of viruses is generally considered to be between 20-250 nanometers (nm), although some viruses can be smaller or…

• A. Rod
• B. Spherical
• C. Tadpole
• D. Helical

Explanation: The shape of TMV virus is rod-shaped or filamentous. TMV stands for Tobacco Mosaic Virus, and it is a type of virus that infects plants…

• A. Yes
• B. No
• C. Provided by cell usually
• D. Provided by virus machinery

Explanation: The attachment of a virus to a host cell does not require energy. The process of virus attachment is typically mediated by specific viral…

• 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.

• 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.

• 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…

• 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…

• A. T-phages
• B. P-phages
• C. Both
• D. None

Explanation: Bacteriophages, or simply phages, are viruses that infect and replicate within bacteria.

• 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…

• 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…

• 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.

• 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.

• 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.

• 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…