All Free Biology MCQs with Answers

• 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.

• 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…

• 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.

• 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

• A. reproduce independently
• B. contain DNA
• C. contain RNA
• D. extracellular

Explanation: Correct Option:AVirions cannot 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…

• 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).

• 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…

• 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.

• A. Pores develop
• B. Glycocalyx layer is formed
• C. Membrane is resynthesised
• D. Viral proteins are acquired

Explanation: Attachment to the host cell is mediated by virion protein(s) binding to specific host surface molecule(s).

• A. RNA
• B. Enzyme
• C. Protective protein coat
• D. All of these options are correct

Explanation: Viroids are infectious agents. They are free RNA and do not contain any cellular components.

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

Explanation: The smallest known virus, according to PTB, is the polio virus. Since this is not in the options, the closest answer is parvovirus because…

• A. 1918
• B. 1917
• C. 1920
• D. 1990

Explanation: The Franco-Canadian microbiologist Félix d'Herelle (1873 to 1949) is credited with the discovery of bacteriophage, a bacterial virus, in…

• A. T2
• B. T4
• C. Both A and B
• D. None

Explanation: The T4 bacteriophage is a member of the family of Myoviridae, which includes bacteriophages with a contractile tail structure.

• A. Rough endoplasmic reticulum
• B. Golgi complex
• C. Nuclear envelop
• D. All of these options are correct

Explanation: Viruses can bud at every stage in the ER-Golgi-cell membrane pathway. As the nucleocapsids assembled or in the process of being built…

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

Explanation: Correct option is A. Satellite viruses are a polyphyletic group of viruses encoding structural components of their virions, but incapable…

• A. Adenovirus
• B. Influenza virus
• C. Poxvirus
• D. Herpes virus

Explanation: Infection with herpes simplex virus (HSV), known as herpes, is common globally.

• A. Complement receptor
• B. Integrin ICAM-1
• C. Acetylcholine
• D. Epidermal growth factor

Explanation: To clarify, the attachment of the rabies virus to host cells involves interactions between viral glycoproteins and specific receptors, and…

• A. ssDNA phage
• B. ssRNA phage
• C. dsDNA phage
• D. dsRNA phage

Explanation: T2 phage is more properly called Enterobacteria phage T2. It is a virulent bacteriophage which infects Escherichia coli bacteria.

• A. Lysogenic cycle
• B. Lytic cycle
• C. Both
• D. None

Explanation: Phages lave a lytic and lysogenic life cycle. In the lysogenic cycle, phages integrate their genetic material into the bacterial…