21. The Immune System

What is complement? How does it cause bacterial lysis? What are some of the other roles of complement?

Which of the following statements about the defensive roles of saliva and gastric juices are true?

All of the following are considered innate body defenses except:

a. Complement

b. Phagocytosis

c. Antibodies

d. Lysozyme

e. Inflammation

What seven defenses, present at birth, provide the body with the defensive capability known as innate (nonspecific) immunity?

Injured tissue releases chemicals called______ that mediate the four cardinal signs of inflammation, which are _____, ______,_____ , and_______.

Capillary permeability increases and plasma proteins leak into the interstitial fluid as part of the inflammatory process. Why is this desirable?

The most beneficial effect of fever is that it

(a) Inhibits the spread of some bacteria and viruses

(b) Increases the metabolic rate by up to 10 percent

(c) Stimulates the release of pyrogens

(d) Achieves a and b

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

Phagocytic cells of innate immunity include NK cells and basophils.

More than one choice may apply.

Chemical mediators of inflammation include

a. Interferon

b. Complement

c. Histamine

d. Antibodies