Question 1

Which of the following best describes the primary function of the lymphatic system in immune defense?

Accepted Answer

It provides a one-way return of interstitial fluid to the blood, filtering pathogens and debris along the way.

Question 2

Which of the following is NOT a characteristic of lymphatic capillaries compared to blood capillaries?

Accepted Answer

They have thicker walls to prevent fluid loss.

Question 3

A patient receives an injection of antibodies after being bitten by a venomous snake. This is an example of:

Accepted Answer

Artificially acquired passive immunity

Question 4

Which of the following immune cells is responsible for directly killing virus-infected cells by releasing perforins and granzymes?

Accepted Answer

Cytotoxic T cells

Question 5

Which antibody class is primarily responsible for resistance against many viruses and bacteria and can cross the placenta?

Accepted Answer

IgG

Question 6

A person develops hives and bronchoconstriction within minutes after eating peanuts. Which immune mechanism is most likely responsible?

Accepted Answer

Immediate hypersensitivity mediated by IgE and mast cells

Question 7

Which of the following is a function of the complement system?

Accepted Answer

Forming pores in pathogen membranes, enhancing phagocytosis, and triggering inflammation

Question 8

Which of the following best explains why tissue transplants are often rejected by the recipient's immune system?

Accepted Answer

The transplanted tissue expresses non-self antigens that activate T cells.

Question 9

Which of the following is a cardinal sign of inflammation caused by increased blood flow and vessel dilation?

Accepted Answer

Redness

Question 10

A child is exposed to chickenpox and develops the disease, then recovers and is immune for life. This is an example of:

Accepted Answer

Naturally acquired active immunity

Question 11

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

Accepted Answer

They are signaling proteins released by virus-infected cells to block viral replication and alert neighboring cells.

Question 12

Which of the following is a property of adaptive (specific) immunity?

Accepted Answer

It produces memory cells that allow for a faster and stronger response upon re-exposure to the same antigen.

Question 13

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

Accepted Answer

Antigen challenge → Cell activation → Clonal selection → Differentiation

Question 14

Which of the following best explains why a person with severe combined immunodeficiency disease (SCID) is highly susceptible to infections?

Accepted Answer

They lack both T and B lymphocytes, impairing both cell-mediated and humoral immunity.

Question 15

Which of the following is a real-life example of delayed hypersensitivity?

Accepted Answer

Allergic contact dermatitis from poison ivy

Question 16

Which of the following is a function of suppressor (regulator) T cells?

Accepted Answer

They turn off the immune response to prevent autoimmunity.

Question 17

Which of the following best describes the process of opsonization?

Accepted Answer

The process by which complement proteins coat pathogens, making them easier for phagocytes to engulf.

Question 18

Which of the following is a likely consequence of blocked lymphatic drainage, as seen in lymphedema?

Accepted Answer

Accumulation of interstitial fluid, swelling, and increased risk of infection

Question 19

Which of the following best explains the role of the thymus gland in immunity?

Accepted Answer

It is where T cells learn to distinguish self from non-self during fetal development.

Question 20

Which of the following is a correct statement about autoimmune diseases?

Accepted Answer

They occur when the immune system fails to recognize self-antigens and attacks the body's own tissues.

Defense Mechanisms of the Immune System: Innate and Adaptive Immunity

Study Guide - Practice Questions