Q: Which equation best represents the calculation of antibody titer in a serological test?

$$Titer = \frac{1}{\text{highest dilution that gives a positive reaction}}$$

Question 1

Which of the following best describes the role of memory T cells in the immune system?

Accepted Answer

They rapidly proliferate and mount a faster cell-mediated response upon re-exposure to a specific antigen.

Question 2

A patient receives an injection of pre-formed antibodies against rabies after being bitten by a potentially rabid animal. Which type of immunity is this an example of?

Accepted Answer

Passive, artificially acquired immunity

Question 3

Which of the following statements correctly contrasts primary and secondary immune responses?

Accepted Answer

The secondary response is faster and produces more antibodies due to the presence of memory cells.

Question 4

Which vaccine type is most likely to confer contact immunity to unvaccinated individuals?

Accepted Answer

Attenuated (live) vaccine

Question 5

What is a major disadvantage of attenuated (live) vaccines?

Accepted Answer

They may revert to a virulent form and cause disease in immunocompromised individuals.

Question 6

Which of the following best describes herd immunity?

Accepted Answer

Protection of unvaccinated individuals due to a high proportion of immune individuals in a population.

Question 7

Which equation best represents the calculation of antibody titer in a serological test?

Accepted Answer

$$Titer = \frac{1}{	ext{highest dilution that gives a positive reaction}}$$

Question 8

Which of the following is a common example of an immunochromatographic assay?

Accepted Answer

Home pregnancy test

Question 9

Which statement correctly describes the difference between direct and indirect fluorescent antibody tests?

Accepted Answer

Direct tests use a labeled antibody to detect antigen, while indirect tests use a labeled secondary antibody to detect the presence of a primary antibody bound to antigen.

Question 10

Which of the following is a risk associated with routine vaccination in healthy populations?

Accepted Answer

Rare occurrence of adverse reactions such as allergic responses

Question 11

Who is credited with performing the first vaccination, and against which disease?

Accepted Answer

Edward Jenner, against smallpox

Question 12

Which vaccine type is often administered with an adjuvant to enhance the immune response?

Accepted Answer

Inactivated (killed) vaccine

Question 13

Which of the following best describes passive immunotherapy?

Accepted Answer

Administration of pre-formed antibodies to provide immediate protection

Question 14

Which of the following is NOT a function of memory B cells?

Accepted Answer

Directly phagocytosing pathogens

Question 15

Which of the following behaviors increases the risk of HIV infection?

Accepted Answer

Sharing needles for intravenous drug use

Question 16

Which statement best describes the relationship between helper T cell population and the progression of AIDS?

Accepted Answer

As helper T cell numbers decrease, the immune system becomes increasingly compromised, leading to AIDS-defining illnesses.

Question 17

Which of the following is a use of serological tests in clinical practice?

Accepted Answer

Diagnosing infections by detecting specific antibodies or antigens

Question 18

Which of the following statements about the germ theory of disease is correct?

Accepted Answer

It proposes that specific microorganisms are the cause of specific diseases.

Question 19

Which of the following equations represents the basic principle of herd immunity threshold?

Accepted Answer

$$H = 1 - \frac{1}{R_0$}$$

Question 20

A patient is exposed to hepatitis B virus and later develops immunity after recovering from the infection. Which type of immunity does this represent?

Accepted Answer

Active, naturally acquired immunity

Immunology and Vaccination: Adaptive Immunity, Vaccines, and HIV/AIDS

Study Guide - Practice Questions

Study Guide - Flashcards