Question 1

Which of the following best describes the main difference between innate and adaptive immunity?

Accepted Answer

Innate immunity is present from birth and responds rapidly, while adaptive immunity develops after exposure and is highly specific.

Question 2

A patient is exposed to a new strain of influenza virus. Which immune response will act first?

Accepted Answer

Innate immunity, because it is active immediately upon infection.

Question 3

Which of the following is NOT a function of the complement system?

Accepted Answer

Directly producing antibodies

Question 4

A person receives a vaccine containing inactivated bacterial toxins. What type of immunity is being developed?

Accepted Answer

Active immunity

Question 5

Which of the following best explains why a person who has recovered from chickenpox is usually immune to future infections by the same virus?

Accepted Answer

Memory cells formed during the primary response enable a faster and stronger secondary response.

Question 6

Which cell type is responsible for activating both the humoral and cell-mediated branches of adaptive immunity?

Accepted Answer

Helper T cell

Question 7

A newborn receives antibodies from its mother through breast milk. This is an example of:

Accepted Answer

Passive immunity

Question 8

Which of the following best describes the role of MHC molecules in adaptive immunity?

Accepted Answer

They present antigen fragments on the cell surface for recognition by T cells.

Question 9

A patient with a genetic defect in the production of helper T cells would likely experience which of the following?

Accepted Answer

Impaired humoral and cell-mediated immune responses

Question 10

Which of the following is a correct match between an antibody class and its function or location?

Accepted Answer

IgG: Most abundant in blood, crosses placenta to provide immunity to fetus

Question 11

Which of the following best describes the process of opsonization?

Accepted Answer

Antibodies bind to pathogens, making them easier for phagocytes to recognize and engulf.

Question 12

A person with lupus erythematosus produces antibodies against their own DNA. This is an example of:

Accepted Answer

An autoimmune disease

Question 13

Which of the following is a key feature of the secondary immune response compared to the primary immune response?

Accepted Answer

It is faster and produces more antibodies due to memory cells.

Question 14

Which of the following best explains why HIV infection leads to AIDS?

Accepted Answer

HIV infects helper T cells, impairing both humoral and cell-mediated immune responses.

Question 15

Which of the following is a real-life example of passive immunity?

Accepted Answer

Receiving antivenom after a snake bite

Question 16

Which of the following best describes the function of cytotoxic T cells?

Accepted Answer

They destroy infected host cells by recognizing antigen fragments presented by MHC I molecules.

Question 17

A person is stung by a bee and experiences a rapid, life-threatening allergic reaction. Which antibody class is most directly involved?

Accepted Answer

IgE

Question 18

Which of the following best explains why moderate exercise is beneficial for immune system function?

Accepted Answer

It improves immune system regulation and response.

Question 19

Which of the following is the correct sequence of events in the activation of a B cell during a primary immune response?

Accepted Answer

Antigen binds to B cell receptor → B cell secretes antibody → Memory cells form

Question 20

Which of the following best describes the role of cytokines in the immune response?

Accepted Answer

They are signaling molecules that enhance the immune response by promoting blood flow and recruiting immune cells.

Chapter 43: Immunology – Innate and Adaptive Immune Responses

Study Guide - Practice Questions