21. The Immune System

Mark the following statements as true or false. If a statement is false, correct it to make a true statement.

NK cells are cytotoxic cells that lyse and kill cancer cells and cells infected with certain viruses.

Which of the following statements about phagosomes and phagolysosomes are true?

The process by which neutrophils squeeze through capillary walls in response to inflammatory signals is called:

a. Diapedesis

b. Chemotaxis

c. Margination

d. Opsonization

Give a function for each of the following:

(l) Interleukins

(m) Tumor necrosis factor

(n) Colony-stimulating factors

More than one choice may apply.

Against which of the following will interferon do some good?

a. Infection of body cells by a virus

b. Circulating free viruses

c. Some types of cancer

d. Bacterial infection

Complement activation promotes all of the following except:

a. Cell lysis

b. Inflammation

c. Opsonization

d. Interferon release

e. Chemotaxis of neutrophils and other cell

Which of the following functions is/are performed by complement proteins?

a. Cell lysis

b. Opsonization

c. Enhancing inflammation

d. Only a and b

e. All of the above

Mark the following statements as true or false. If a statement is false, correct it to make a true statement.

d.Interleukin-1 is a cytokine that prevents viral replication in infected cells.

Where are bacteria killed by enzymes and toxic substances once ingested by a white blood cell?

Eileen presents with flu-like symptoms, including fever, chills, and body aches.

c. What might it mean if lymphocytes instead of neutrophils were elevated? Explain your reasoning.

Interferons are referred to as antiviral proteins. What stimulates their production, and how do they protect uninfected cells? Which cells of the body secrete interferons?