Question 1

Which of the following is considered a first line of defense in the human immune system, and is classified as a nonspecific anatomical barrier?

Accepted Answer

Skin and mucous membranes

Question 2

Which type of immunity is acquired when a person receives antibodies from their mother through breast milk?

Accepted Answer

Passive natural immunity

Question 3

During an inflammatory response, which of the following events occurs first at the site of injury?

Accepted Answer

Vasodilation and increased blood flow

Question 4

Which cell type is primarily responsible for producing antibodies in the adaptive immune response?

Accepted Answer

Plasma cells

Question 5

A patient receives an injection of pre-formed antibodies to treat rabies exposure. What type of immunity is this?

Accepted Answer

Passive artificial immunity

Question 6

Which of the following best describes the role of Major Histocompatibility Complex (MHC) molecules in the immune response?

Accepted Answer

They present antigen fragments to T cells

Question 7

Which of the following is a function of cytotoxic T cells ($T_C$ cells) in the immune system?

Accepted Answer

Destruction of virus-infected cells

Question 8

Which of the following scenarios would most likely result in active artificial immunity?

Accepted Answer

Administration of a vaccine

Question 9

Which of the following statements about the inflammatory response is correct?

Accepted Answer

It involves increased permeability of blood vessels and migration of phagocytes

Question 10

A newborn receives antibodies from maternal blood crossing the placenta. This is an example of:

Accepted Answer

Passive natural immunity

Question 11

Which of the following best explains why vaccines provide long-lasting protection against specific diseases?

Accepted Answer

Vaccines stimulate the production of memory cells

Question 12

Which of the following is NOT a characteristic of the second line of defense in the immune system?

Accepted Answer

It is specific to particular pathogens

Question 13

Which immune cell type is responsible for activating both B cells and cytotoxic T cells by releasing cytokines?

Accepted Answer

Helper T cells ($T_H$ cells)

Question 14

Which of the following is a correct sequence of events in the inflammatory response?

Accepted Answer

Vasodilation → Increased permeability → Migration of phagocytes → Tissue repair

Question 15

Which of the following best describes the difference between active and passive immunity?

Accepted Answer

Active immunity results from exposure to antigens and leads to memory cell formation; passive immunity involves receiving antibodies from another source

Question 16

Which of the following immune responses is most likely to be impaired in a patient with a genetic defect in MHC class II molecules?

Accepted Answer

Activation of helper T cells ($T_H$ cells)

Question 17

A person recovers from a viral infection and is protected from future infections by the same virus. What type of immunity is this?

Accepted Answer

Active natural immunity

Question 18

Which of the following is a function of memory cells in the adaptive immune system?

Accepted Answer

They enable a faster and stronger response upon re-exposure to the same antigen

Question 19

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

Accepted Answer

They inhibit viral replication and activate immune cells

Question 20

A patient receives a flu vaccine containing inactivated virus. Which equation best represents the process of antibody production following vaccination?

Accepted Answer

$	ext{Antigen} + 	ext{B cell} ightarrow 	ext{Plasma cell} ightarrow 	ext{Antibody}$

Unit 4 Review: Immunity and Immune Responses

Study Guide - Practice Questions

Study Guide - Flashcards