Immunity

Question 0

Leukocytes:

Function

Answer 0

1. Involved in nonspecific and Specific immune system responses
2. Detect, attack, and destroy anything that is recognized as foreign
3. Normal number is 4,500-10,000 cells per cubic millimeter

Question 1

Functions of the immune system:

Answer 1

1. Defends and protects the body from infection
2. Removes and destroys damaged or dead cells
3. Identifies and destroys malignant cells. There by preventing their further development into tumors.

Question 2

Leukocytes:

3 Major groups

Answer 2

1. Granulocytes
2. Monocytes
3. Lymphocytes

Question 3

Granulocytes:

Answer 3

1. 60-80% of total number of blood leukocytes
2. Cytoplasm has a granular appearance
3. Short life span, hours-days
4. Play a key role in protecting body form harmful microbes during acute inflammation

Question 4

3 Types of Granulocytes:

Answer 4

1. Neutrophils
2. Eosinophils
3. Basophils

Question 5

Granulocytes:

Neutrophils

Answer 5

1. Most plentiful of granulocytes
2. Phagocytic Cells- engulf and destroy foreign agents
3. 1st phagocytic cell to arrive at the site of invasion
4. Segs- mature, Bands- immature

Question 6

Granulocytes:

Eosinophils

Answer 6

1. Phagocytic cells
2. Found in Respiratory, and GI tracts
3. Protect body from parasitic worms
4. Also involved in hypersensitivity response, inactivating some of the inflammatory chemicals released during inflammation.

Question 7

Granulocytes:

Basophils

Answer 7

1. NOT phagocytic

2. Granules contain proteins and chemicals such as heparin, histamine, bradykinin, serotonin, and leukotrienes

Question 8

Antigen-Presenting Cells (APCs)

Answer 8

1. Activate immune responses in both B and T lymphocytes
2. Recognize foreign matter
3. Actively phagocytic

Question 9

Antigen-Presenting Cells (APCs)

3 Types

Answer 9

1. Monocytes
2. Macrophages
3. Dendritic cells

Question 10

Monocytes:

Answer 10

1. Largest of the leukocytes
2. Migrate to various tissues and remain for months or even years until activated
3. Activate immune response against chronic infections- TB, Virals,

Question 11

Macrophages:

Answer 11

1. Differentiated by tissues in which they reside: Histiocytes- loose connective tissue, Kupffer cells- liver, alveolar macrophages, microglia- brain
2. Drawn to inflammation by Chemotaxis

Question 12

Lymphocytes:

Answer 12

1. The principal effector and regulator cells of specific immune responses to protect the body from microorganisms, foreign tissue, and cell mutations or alterations.
2. Monitor body for cancerous cells and attempt to destroy them.
3. Memory cells-> aquired immunity

Question 13

3 Types of Lymphocytes

Answer 13

1. T lymphocytes (T Cells)
2. B lymphocytes (B Cells)
3. Natural killer cells (NK cells or null cells)
   None of these cells act independently, their functions are closely related.

Question 14

T Cells

Answer 14

1. Mature in the Thymus gland

2. On contact with APC mature into Helper T Cells (CD4), Cytotoxic T cells (CD8), and memory T cells.

Question 15

B Cells

Answer 15

1. Mature in Bone marrow
2. On contact with an antigen B cells are activated and mature into plasma cells, which secrete antibodies, or memory cells

Question 16

Natural Killer Cells

Answer 16

1. Large granular cells found in the spleen, lymph nodes, bone marrow, and blood.
2. Play important role in destruction of early malignant cells.
3. Do not require APCs to become activated and kill cancer cells, virus infected cells, and cells infected with microbes.

Question 17

Antigens

Answer 17

Proteins found on the cell membrane or cell wall of microbes or tissues. The portion of an antigen that incites a specific immune response is called an antigenic determinant site (EPITOPE)

Question 18

B Cell (Humoral Branch)

Answer 18

1. Eliminates extracellular antigens, such as bacteria, bacterial toxins, free viruses, through production of antibodies (molecules that bind with the antigen and deactivate it)
2. Antibodies are found in serum, body fluids, and certain tissues
3. When 1st exposed, the B cell produces antibodies that react specifically to that antigen (approx 3 days= Primary Immune Response)
4. Subsequent encounters with the antigen trigger memory cells-> resulting in a secondary immune response (24 hrs.)

Question 19

5 Classes of Antibodies (immunoglobulins)

Answer 19

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

Question 20

IgG Antibodies

Answer 20

1. The major immunoglobulin- response is longer and stronger
2. Results from secondary exposure to the foreign antigen
3. Responsible for antiviral and antibacterial activity
4. Passes through placental barrier and provides early immunity for the newborn.

Question 21

IgA Antibodies

Answer 21

1. Found in secretions of Respiratory, GI, and GU tracts, tears, and saliva
2. Protects mucous membranes from invading organisms
3. Does not pass placental barrier
4. If deficiency of IgA , prone to autoimmune disorder

Question 22

IgM antibodies

Answer 22

1. produced 48-72 hours after antigen enters body, responsible for primary immunity
2. Produces antibody activity against rheumatoid factors,& ABO
3. Doesn’t pass placental barrier.

Question 23

IgD Antibodies

Answer 23

UNKNOWN! :)

Question 24

IgE Antiobodies

Answer 24

1. Increases during allergic reactions and anaphylaxis

2. Useful in combating parasitic infections

Question 25

T lymphocytes (Cell mediated/ cellular immune response)

Answer 25

1. Detects intracellular pathogens, such as viral-infected cells, cancer cells, and foreign tissue.
2. Acts at the cellular level by attacking antigens directly and activating B cells.

Question 26

Normal Changes of Aging

Answer 26

1. Decrease in immune response & lowered resistance to infection
2. Poor response to immunizations
3. Autoantibodies are more common-> increase in autoimmune responses.