Question 1

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

Accepted Answer

Innate defenses provide immediate, nonspecific protection, while adaptive defenses target specific pathogens and take longer to respond.

Question 2

A patient has a genetic defect that prevents the production of lysozyme in their saliva and tears. Which of the following would most likely result from this defect?

Accepted Answer

Increased susceptibility to bacterial infections in the eyes and mouth.

Question 3

Which of the following is NOT a function of inflammation?

Accepted Answer

Directly produces antibodies to neutralize pathogens.

Question 4

During the process of phagocytosis, what is the correct sequence of events after a phagocyte recognizes a pathogen?

Accepted Answer

Phagocyte engulfs the pathogen, forms a phagosome, fuses with a lysosome, digests the pathogen, and expels waste.

Question 5

A patient presents with a fever after a bacterial infection. Which of the following best explains the physiological benefit of a moderate fever?

Accepted Answer

It causes the liver and spleen to sequester iron and zinc, limiting bacterial growth.

Question 6

Which of the following best describes the role of natural killer (NK) cells in the immune system?

Accepted Answer

They induce apoptosis in cancer and virus-infected cells that lack 'self' cell surface receptors.

Question 7

A researcher is studying the complement system. Which of the following statements about complement activation is correct?

Accepted Answer

All complement activation pathways converge at the cleavage of C3 into C3a and C3b.

Question 8

Which of the following is a direct result of increased vascular permeability during inflammation?

Accepted Answer

Exudate containing clotting factors and antibodies leaks into the tissue, causing local swelling (edema).

Question 9

A patient with tuberculosis develops granulomas in their lungs. What is the primary reason for granuloma formation in this context?

Accepted Answer

To wall off bacteria that resist digestion by macrophages, preventing their spread.

Question 10

Which of the following best explains the process of opsonization in the immune response?

Accepted Answer

Pathogens are coated with antibodies or complement proteins, enhancing their recognition and ingestion by phagocytes.

Question 11

A mutation causes a patient's neutrophils to lack the ability to produce defensins. Which of the following would most likely be impaired?

Accepted Answer

The ability to pierce the membrane of pathogens, reducing microbial killing.

Question 12

Which of the following is a cardinal sign of acute inflammation?

Accepted Answer

Redness (rubor)

Question 13

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

Accepted Answer

They stimulate neighboring cells to produce proteins that block viral replication and degrade viral RNA.

Question 14

A patient has a wound that is healing slowly and is not showing signs of redness, heat, or swelling. Which of the following is most likely impaired in this patient?

Accepted Answer

The inflammatory response.

Question 15

Which of the following best explains why the skin is an effective first line of defense against pathogens?

Accepted Answer

It contains keratin, which is resistant to weak acids, bases, bacterial enzymes, and toxins.

Question 16

Which of the following steps in phagocyte mobilization involves the movement of neutrophils through the capillary wall into the injured tissue?

Accepted Answer

Diapedesis

Question 17

A scientist is studying the membrane attack complex (MAC) formed by complement proteins. What is the primary function of the MAC?

Accepted Answer

To form a hole in the pathogen's membrane, causing cell lysis.

Question 18

Which of the following best describes the role of pattern recognition receptors (PRRs), such as Toll-like receptors (TLRs), in innate immunity?

Accepted Answer

They bind to unique molecular patterns on microbes, triggering immune responses.

Question 19

A patient is exposed to a virus, and their cells begin to secrete interferon-alpha ($$\alpha). $$Which of the following is the most likely effect on neighboring cells?

Accepted Answer

Neighboring cells will be stimulated to produce proteins that block viral replication.

Question 20

Which of the following is a benefit of edema during inflammation?

Accepted Answer

It delivers clotting proteins and complement to the area, forming a fibrin mesh that isolates the injury.

Innate and Adaptive Defenses of the Immune System: Anatomy & Physiology Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards