Chapter 32

Question 1

What is an antigen?

Answer 1

-unique group of molecules of surface used to recognize them

Question 2

What is immunocompetence?

Answer 2

-the ability to activate a response to a bad antigen

Question 3

What are the two major categories of immune mechanisms?

Answer 3

• innate immunity

- adaptive immunity

Question 4

Describe innate immunity. What is it called?

Answer 4

• in place before a person is exposed to an antigen
• called nonspecific immunity
• faster

Question 5

What composes innate immunity?

Answer 5

• epithelial barrier cells
• phagocytic cells (neutrophils and macrophages)
• natural killers
• cytokines

Question 6

Describe adaptive immunity. What is it called?

Answer 6

• recognizes specific threatening agents and adapt by targeting their activity against those antigens
• called specific immunity
• takes time, memory cells

Question 7

What composes adaptive immunity?

Answer 7

• t cells

- b cells

Question 8

What is species resistance?

Answer 8

• genetic characteristics common to a species that provide resistance to a certain pathogen
• every member of species is resistant

Question 9

What makes up the first line of defense?

Answer 9

• mechanical: skin

- chemical barriers: sebum, mucus, enzymes, hydrochloric acid

Question 10

What are the second lines of defense?

Answer 10

• inflammation
• fever
• phagocytosis
• NK cells
• interferon proteins
• complement system

Question 11

What is inflammation?

Answer 11

• redness, pain, heat, swelling

- damaged tissue release chemotaxis that attract wbc

Question 12

What are inflammation mediators?

Answer 12

• histamine
• kinis
• prostaglandins
• leukotrienes
• interleukins

Question 13

What are the three stages of inflammation?

Answer 13

• vasodilation and increased permeability
• phagocyte emigration (creates pus; diapedesis)
• tissue repair

Question 14

What is diapedesis?

Answer 14

-passage of blood clot through intact wall of capillaries

Question 15

What is fever?

Answer 15

-state of abnormally high body temperature

Question 16

What chemical causes fever?

Answer 16

-prostaglandins

Question 17

What is phagocytosis?

Answer 17

-ingestion and destruction of microorganisms and small particles

Question 18

Which white blood cells participate in phagocytosis?

Answer 18

• neutrophils

- macrophages (monocytes)

Question 19

What are the different kinds of macrophages? Location?

Answer 19

• wandering

- fixed (skin, liver, lungs, nervous system, secondary lymph organs)

Question 20

What are the five stages of phagocytosis?

Answer 20

• chemotaxis via diapedesis
• adherence
• ingestion
• digestion
• release/presentation

Question 21

What is an antigen-presenting cell? Why are they important?

Answer 21

• after digestion of particle, a phagocyte displays bits of protein on its surface
• important bridge between innate and adaptive immunity

Question 22

What are natural killer cells?

Answer 22

• lymphocytes

- kills tumor cells and cells infected with a virus

Question 23

How do NK cells recognize abnormal cells? Function?

Answer 23

• killer-activating receptor: binds to any cell

- killer-inhibiting receptor: binds to the MHC (only self cells)

Question 24

What is the major histocompatibility complex?

Answer 24

• MHC that identifies cell as “self”

- helps body not attack self

Question 25

What chemical do NK cells secrete? What does it do?

Answer 25

• perforin

- makes membrane leaky causing apoptosis

Question 26

What are the two classes of MHC? Where do you find them?

Answer 26

• class I: on surface of all body cells except rbc

- class II: on surface of antigen presenting cells

Question 27

What is an interferon? Function?

Answer 27

• released by cells infected with virus
• interfere with viral replication
• alarm neighboring cells

Question 28

What is the compliment system? Function?

Answer 28

• normally inactive enzymes in blood and on cell surfaces
• activated by complement cascade
• causes lysis of foreign cell that triggered response
• triggers inflammatory response