The immune System

Question 1

• Predominant Ab in secondary responses

- only Ab that cross the placenta ( most abundant Ig in NBs)

Answer 1

IgG

Question 2

• main Ig produced early in the primary reponse
• present on the surface of virtually all uncommited B Cells
• pentamer (10 identical antigen binding sites) highest avidity
• most efficient Ig in agglutination, compliment fixation
• can be produced by the fetus undergoing an infection

Answer 2

IgM

Question 3

Mechanisms of action of antibodies (2)

Answer 3

1. Direct action of antibodies on invading agents

2. Activation of compliment system

Question 4

Direct action of antibodies on invading agents(4)

Answer 4

1. Agglutination
2. Precipitation
3. Neutralization
4. Lysis

Question 5

Multiple large particles with antigens on their surfaces bound into a clump

Answer 5

Agglutination

Question 6

Molecular complex of antigen and antibody becomes so large that it i rendered insoluble and precipitates

Answer 6

Precipitation

Question 7

Antibodies cover toxic sites of antigenic agents

Answer 7

Neutralization

Question 8

Potent antibodies are occasionally capable of directly attacking membranes of agents and cause rupture

Answer 8

Lysis

Question 9

________________ collective term for a system of about 20 proteins many of which are enzyme precursor

Answer 9

Complement

Question 10

• Ig typically increased during helminth infection

- the Fc region binds to feceptor on the surface of mast cells , basophils, and eosinophils

Answer 10

IgE

Question 11

• acts as antigen receptor when present on the surface of certain B cells
• trace amount in serum

Answer 11

IgD

Question 12

• Mechanisms of Innate immunity(2)

Answer 12

a. Physiologic barriers at the portal at the portal of entry

b. Innate immunolgic mechanisms

Question 13

1. able to phagocytize 3 to 20 bacteria( have proteolytic enzymes)
2. Phagocytize as many as 100 bacteria( have proteolytic enzmes and lipases)
3. Both can be also kill bacteria by using _______________ ( superoxide, hydrogen peroxide(h2o2) and using hydroxyl ions (-OH)

Answer 13

1. Neutrophils
2. Macrophages
3. Oxidizing agents

Question 14

A. Types of immunity

B. types of___________ in answer A

Answer 14

A. 1.Innate immunity/ inborn/ non-specific defence mechanism
2. Acquired/ Adaptive/ specific defence mechanism

B.

Question 15

Most common systemic manifestation of inflammatory response anda cardinal symptom of infectious disease

Answer 15

Fever

Question 16

Thermoregulatory center

Answer 16

Hypothalamus

Question 17

Stimulate cells to produce antiviral proteins ( nonspecific response)

Target cells = most cell types

Answer 17

Interferons

Question 18

Stimulate proliferation of neutrophils and monocytes

target cells = bone marrow

Answer 18

Colony stimulating factors

Question 19

Facilitate accumulation of leukocytes at sites of endothelial cells leukocytes injury and inflammation

target cells= neutrophils and other leukocytes

Answer 19

Chemokines

Question 20

Stimulate proliferation and secretion of cytotoxic compounds

target cells= NK cells and macrophages

Answer 20

Interferon gamma

Question 21

Stimulate proliferation, promote conversion to plasma cells

target cells = helper t cells; cytotoxic T cells; NK cells ; B cells

Answer 21

Interleukin 2

Question 22

Stimulate IL- 2 secretion and IL-2 receptor expression; induce fever; stimulate systemic response to inflammation, infection; and injury

Target cell= helper T cells; certain brain cells; numerous systemic system

Answer 22

Interleukin I, tumor necrosis factor interleukin 6

Question 23

• Main Ig in secretions ( milk, tears, saliva and on secretions of respiratory, intestinal and genital tracts
• It protects mucus membrane from bacteria and viruses
• exist as monomer in serum; dimer in tissue

Answer 23

IgA