Q. What is the function of memory cells in the immune system?
A.To produce immediate immune responses
B.To remember past infections and respond quickly upon re-exposure
C.To activate macrophages
D.To secrete cytokines
Solution
Memory cells are long-lived cells that remember past infections and enable a faster and more effective response upon re-exposure to the same pathogen.
Correct Answer: B — To remember past infections and respond quickly upon re-exposure
Q. What is the main purpose of the complement system?
A.To produce antibodies
B.To enhance phagocytosis and lyse pathogens
C.To activate T cells
D.To produce cytokines
Solution
The complement system enhances phagocytosis and can directly lyse pathogens, playing a vital role in the immune response.
Correct Answer: B — To enhance phagocytosis and lyse pathogens
Q. What is the primary function of B cells in the immune response?
A.Phagocytosis of pathogens
B.Production of antibodies
C.Activation of T cells
D.Release of cytokines
Solution
B cells are primarily responsible for the production of antibodies, which are crucial for the humoral immune response.
Correct Answer: B — Production of antibodies
Q. What is the role of antigen-presenting cells (APCs) in the immune response?
A.To produce antibodies
B.To present antigens to T cells
C.To directly kill pathogens
D.To secrete cytokines
Solution
Antigen-presenting cells (APCs) process and present antigens to T cells, initiating the adaptive immune response.
Correct Answer: B — To present antigens to T cells
Q. What role do T helper cells play in the immune response?
A.Directly kill infected cells
B.Help activate B cells and cytotoxic T cells
C.Produce antibodies
D.Engulf and digest pathogens
Solution
T helper cells assist in activating B cells and cytotoxic T cells, playing a central role in coordinating the immune response.
Correct Answer: B — Help activate B cells and cytotoxic T cells
Q. Which cytokine is primarily involved in the activation of T cells?
A.Interleukin-1
B.Interleukin-2
C.Tumor necrosis factor-alpha
D.Interferon-gamma
Solution
Interleukin-2 is crucial for T cell proliferation and activation, making it a key cytokine in the immune response.
Correct Answer: B — Interleukin-2
Q. Which of the following is a characteristic of adaptive immunity?
A.Immediate response
B.Non-specific response
C.Memory and specificity
D.Physical barriers
Solution
Adaptive immunity is characterized by its memory and specificity, allowing for a tailored response to specific pathogens.
Correct Answer: C — Memory and specificity
Q. Which of the following is NOT a component of the innate immune system?
A.Macrophages
B.Natural killer cells
C.Antibodies
D.Complement proteins
Solution
Antibodies are part of the adaptive immune system, while macrophages, natural killer cells, and complement proteins are components of the innate immune system.
Correct Answer: C — Antibodies
Q. Which type of immune response is characterized by the production of antibodies?
A.Cell-mediated immunity
B.Humoral immunity
C.Innate immunity
D.Adaptive immunity
Solution
Humoral immunity is characterized by the production of antibodies by B cells in response to antigens.
Correct Answer: B — Humoral immunity
Q. Which type of immunity is provided by vaccination?
A.Innate immunity
B.Passive immunity
C.Active immunity
D.Cell-mediated immunity
Solution
Vaccination stimulates the immune system to produce an active immune response, leading to the development of active immunity.
