All Free Biology MCQs with Answers

2661. All of the following are viral diseases except:

• A. Influenza
• B. Polio
• C. Mumps
• D. Tetanus

Explanation: So, among the options, "Tetanus" is not a viral disease; it's a bacterial infection caused by Clostridium tetani. The other three options (Influenza, Polio, and Mumps) are indeed viral diseases.

2662. Hepatitis A virus is:

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

Explanation: Viruses can be classifying on the bases of genome, HAV contains single standard RNA. HBV contains DNA and HCV contains RNA.Hepatitis A virus has a single-stranded RNA genome, which means its genetic material consists of a single strand of RNA.

2663. HAV is transmitted through:

• A. Blood
• B. Scrum
• C. Fecal oral route
• D. Syringes

Explanation: The virus spreads by the fecal-oral route, and infections often occur in conditions of poor sanitation and overcrowding.

2664. Poliomyelitis affects:

• A. Sensory neuron
• B. Brain
• C. Motor neuron
• D. Muscles

Explanation: Poliovirus replicates in oropharynx, intestine and spread through blood to nervous system. Poliovirus replicates in motor neuron localed in spinal cord. Death of these cell result in paralysis.

2665. Small pox is caused by poxvirus which is:

• A. DNA Naked Virus
• B. RNA Enveloped Virus
• C. RNA Naked Virus
• D. DNA Enveloped Virus

Explanation: Poxvirus is DNA enveloped virus, which caused epidemic in the past causing samII pox, but now this disease, has been eradicated from the world.

2666. Mad cow disease is caused by:

• A. Virus
• B. Virion
• C. Viroid
• D. Prion

Explanation: Prions are infectious particles made up of only proteins containing information for replication and cause mad cow infection and mysterious brain infection in man.

2667. Hepatitis C is also known as:

• A. Infections Hepatitis
• B. Scrum Hepatitis
• C. Infusion Hepatitis
• D. Delta Hepatitis

Explanation: Hepatitis C virus is RNA enveloped virus that causes infusion hepatitis. Hepatitis A is known as infectious hepatitis, while the common name of hepatitis B is scrum hepatitis.

2668. Pigs are reservoir for:

• A. Hepatitis A
• B. Hepatitis B
• C. Hepatitis C
• D. Hepatitis E

Explanation: Most recent work of Halbur and coworker (2001) reveals that pig could be the source of infection of hepatitis E.

2669. The enzyme involved in viral replication are synthesized:

• A. By the host cell
• B. On the interior surface of viral membrane
• C. On the viral ribosomes
• D. On the interior surface of viral coat

Explanation: Viruses are obligate intracellular parasites. They use host biosynthetic machinery for protein synthesis.

2670. Ribavirin is used to treat:

• A. Hepatitis C
• B. Hepatitis B
• C. Hepatitis A
• D. Hepatitis D

Explanation: Ribavirin is an antiviral medication used in combination with other drugs to treat Hepatitis C. It is often part of a regimen for managing chronic Hepatitis C infections.