Immunity

Question 1

B cell:

Answer 1

make antibodies and mediate humoral immunity

Question 2

Cytolytic T-lymphocytes (CD8)

Answer 2

attack and kill target cells - specificity determined by presence of antigen molecules on surface of target cell and receptors for antigen on T-cell

Question 3

Helper t-lymphocytes (CD4)

Answer 3

antibody production by B-cells, release factors that promote delayed-type hypersensitivity, and participate in activation of cytolytic t-cells

Question 4

Macrophages

Answer 4

phagocytosis; activate t-cells (CD4 and CD8); final mediators of delayed-type hypersensitivity

Question 5

Mast cells and basophils

Answer 5

mediate immediate hypersensitivity reactions; release histamine, heparin and other compounds that cause hypersensitivity reactions

Question 6

neutrophils

Answer 6

phagocytize bacteria and other foreign particles that have been tagged with IgG antibodies; important effectors of humoral immunity; contribute to inflammation

Question 7

eosinophils

Answer 7

attack and destroy foreign particles coated with IgE antibodies; contribute to tissue injury and inflammation associated with hypersensitivity reactions

Question 8

Antibodies

Answer 8

family of structurally related glycoproteins that mediate humoral immunity;

produced by lymphocytes;

bind with specific antigens

Question 9

Five classes of antibodies

Answer 9

1. IgG
2. IgE
3. IgD
4. IgA
5. IgM

Question 10

Antigens

Answer 10

molecules that induce specific immune responses by becoming targets of those immune responses

Question 11

How do antigens and antibodies work together?

Answer 11

Antibodies recognize and bind to selected small portions of the antigen referred to as epitopes or antigenic determinants

Question 12

Characteristic Features of the Immune Response (5)

Answer 12

1. Specificity
2. Diversity
3. Memory
4. Time limitation
5. Selectivity for antigens of nonself origin

Question 13

Phases of Immune Response (3)

Answer 13

1. recognition phase
2. activation phase
3. effector phase

Question 14

Phases of Immune Response: Recogntion

Answer 14

mature lymphocyte encounters matching antigen

antigen recognition by B-cells and T-cells

Question 15

Phases of Immune Response: Activation

Answer 15

antigen activates lymphocyte which then undergoes proliferation and differentiation

some cells differentiate into cells that actively participate in attacking source of antigen

others differentiate into memory cells

Question 16

Phases of Immune Response: Effector

Answer 16

elimination of antigen

cell mediated immunity: antigen bearing target cells lysed by CD8 cells or ingested by macrophages

antibody-mediated immunity: target cells primed for attack by phagocytes or complement system

Question 17

Major histocompatibility complex molecules

Answer 17

group of genes that codes for MHC molecules that become expressed on surface of all cells

key role in activation of CD8 cells

guide CD8 cells toward target cell

basis for distinguishing between self and non-self

Question 18

Class I MHC molecules

Answer 18

on all cells except erythrocytes

located on surface of antigen-presenting cells

help initiate immunity by presenting antigen to cytotoxic t-cells*

Question 19

Class II MHC molescules

Answer 19

found primarily on B-cells and APCs

located on surface of APCs

help initiate immune responses by presenting antigen to helper t-cells (CD4)*

Question 20

Cytokines

Answer 20

any mediator molecule other than an antibody released by an immune system cell

note: people who are obese are at greater risk for CV events due to cytokines

Question 21

Lymphokine

Answer 21

cytokine released by a lymphocyte

Question 22

Monokine

Answer 22

Cytokine released by mononuclear phagocytes (monocyte or macrophage)

Question 23

Interferons

Answer 23

proteins that are part of your natural defences

tell your immune system that germs or cancer are in your body

trigger immune cells to fight invaders

“interfere with viruses and keep them from multiplying’