Question 1

When a pathogen causes redness, heat, swelling, and pain, the process is called:

Accepted Answer

Inflammation is characterized by redness, heat, swelling, and pain. If the irritant is caused by a pathogen, the inflammation is called an infection.

Question 2

Which of the following includes mechanical barriers, chemical barriers, and reflexes?

Accepted Answer

Nonspecific immunity is also called innate immunity because we are born with certain defensive mechanisms that do not require prior exposure to the pathogen or foreign agent. The first line of defense includes mechanical barriers, chemical barriers, and reflexes.

Question 3

Which of the following is most related to pus?

Accepted Answer

Two important phagocytes are the neutrophils and monocytes. The neutrophils are small, motile and travel to the site of infection quickly; they engage the pathogen aggressively and most die in battle becoming part of the cellular debris and pus.

Question 4

Leukocytes "go" to the site of infection. Which of the following is descriptive of this activity?

Accepted Answer

The process of squeezing through tiny gaps is called diapedesis. Chemicals released by injured cells attract them to the injured site. The signaling is called chemotaxis.

Question 5

Which of the following is most descriptive of the Kupffer cell?

Accepted Answer

The Kupffer cells in the liver are fixed to the walls of the large capillaries called sinusoids.

Question 6

The "big-eating" fixed phagocytes located in the liver, spleen, and lymph nodes:

Accepted Answer

The macrophages that become fixed in a particular organ often take on a variety of names. The liver, spleen, lungs, and lymph nodes have a particularly rich supply of phagocytes.

Question 7

Fever-producing substances (pyrogens):

Accepted Answer

As phagocytes perform their duty, they release fever-producing substances called pyrogens (from the Latin word for "fire").

Question 8

Interferons are:

Accepted Answer

Interferons are a group of proteins secreted by cells infected by a virus. The interferons diffuse to surrounding cells where they prevent viral replication, thereby protecting neighboring cells.

Question 9

Your own cells and secretions are recognized by your body as nonantigenic. What is this self-recognition called?

Accepted Answer

Recognition of self is called immunotolerance.

Question 10

Antibody-mediated immunity:

Accepted Answer

B cells interact with the antigen indirectly, through the secretion of antibodies. This response is called antibody-mediated immunity (AMI).

Quiz 21: Immune System