This set of Virology MCQs focuses on “Interaction between Animal Viruses and Hosts”.
1. Which of the following is not the part of Koch’s postulate?
a) The microorganism is always found in diseased animals
b) The microorganism secretes toxin in culture
c) The microorganism is never found in healthy animals
d) The microorganism causes disease in healthy animals
Explanation: Koch’s postulate includes that the suspected agent must be present in a particular tissue in every case of the disease, the agent must be isolated and grown in pure culture, and pure preparations of agent must cause the same disease when they are introduced into healthy subjects.
2. Which of the following is not the criteria for the classification of virus-host interactions?
a) Production of infectious progeny
b) Size of the virus
c) Signs and symptoms
d) Duration of infection
Explanation: The categories of virus-host interaction are distinguished on four criteria: the production of infectious progeny, whether or not the virus kills its host cell, if there are observable signs and symptoms, and the duration of infection.
3. Which of the following infection is specific to only cell and not the whole organism?
Explanation: Null infection is an infection that occurs at the cell level. Acute, subclinical, persistent, chronic, latent, and tumorigenic are the types of infection that occur at the whole organism level.
4. In which of the following infection the infecting dose of virus is small?
Explanation: The infection in which the infecting dose of virus is small and the virus goes through many rounds of replication is called acute infection and this infection spreads from first infected cells to new susceptible cells. It is analog to acutely cytopathogenic infections.
5. Influenza virus infects _______________
b) respiratory system
Explanation: Influenza virus infects the respiratory system and causes fever, aching, catarrh, etc. Whereas the hepatitis virus infects the liver. This specificity is achieved largely through the presence of cell receptors on only certain cells in the body.
6. Which of the following is also known as a silent infection?
Explanation: Subclinical infections are also known as silent infections or inapparent infections. They are the most common infections and no signs and symptoms occur of the disease. These are the same as acute infections.
7. Human Papillomavirus causes the cancer of ___________
b) lymphoid tissue
Explanation: Human papillomavirus (HPV) is a group of viruses that causes cervical cancer. HPV infection also passes through the skin to skin contact. It is most common in the United States.
8. Cell lysis is associated with necrosis.
Explanation: Apoptosis contrasts with cell lysis or necrosis where the cells disintegrate and its contents are released. The cells which undergo necrosis are inflammatory as the necrotic products are inflammatory in the whole animal.
9. T cells are the main defense against primary infections.
Explanation: T cells are the main defense against primary infections. T cells in particular CD8+ cytotoxic T cells and antibodies are the main defense against primary infections.
10. Which of the following virus causes the cancer of lymphoid tissue of the jaw?
Explanation: Epstein-Barr virus (EBV), a herpes virus, causes the cancer of lymphoid tissue of jaw which is also called Burkitt’s lymphoma. It also causes nasopharyngeal carcinoma.
11. Which of the following antibody is present in breast milk?
Explanation: IgA antibody is present in breast milk. It helps the infants to fight against microbes and several infectious agents. Breast milk is preferred for infants because cow milk does not contain antibodies.
Sanfoundry Global Education & Learning Series – Virology.
To practice MCQs on all areas of Virology, here is complete set of 1000+ Multiple Choice Questions and Answers.