BIO -Immune System

Question 1

(4) Cell identification & particles of Immune System

Answer 1

Markers (antigens): identify cells as virus or immune particle
Self-markers: unique molecules that identify cell as “self”
Non-self-markers: foreign/abnormal cells labeled as “non-self”
Self-tolerance: ability of immune system to attack abnormal cells but spare normal cells

Question 2

Innate immunity

Answer 2

epithelial barrier cells, phagocytes (neutrophils, macrophages, dendritic cells), NKC
Quick response

Question 3

Species resistance

Answer 3

genetic characteristics of an organism/specie that defend against pathogens (innate immunity)

Question 4

(3) Line of Defenses - Innate Immunity

Answer 4

1st: Mechanical and chemical barriers
2nd: Inflammatory response / Fever / phagocytosis
3rd: Natural Killer Cells (NK)
- carry out adaptive immunity with B & T cells

Question 5

1st Line of defense

Answer 5

Mechanical and chemical barriers

- skin, enzymes, hydrochloric acid

Question 6

2nd Line of defense

Answer 6

1) Inflammatory response
- Chemotaxis: movement of cells to area by chemical attraction
- Diapedesis: immune cells squeeze through vessel walls
- cardinal signs of inflammation
- redness, pain, swelling
2) Fever - incr immune fxn & inhibit pathogens
3) Phagocytosis - ingest/destruction of cells
- occurs in both innate/adaptive immunity
- Neutrophils (most numerous- 1st arrive)
- Macropage (large)
- Dendritic cell (antigen presenting)

Question 7

3rd Line of defense

Answer 7

Natural Killer (NK) cells - lymphocytes that kill tumor cells and cells infected by viruses
   - don't require activation by foreign antigen
Part of adaptive immunity

Question 8

Negative Feedback Loop of Inflammatory Response

Answer 8

Bacterial infx > tissue damage > inflamm mediators released (chemotaxis, diapedesis, incr blood flow, incr vascular permeability) > incr leukocytes/mediators to tissue > bacteria contained/destroyed (phagocytize) > tissue repair or additional mediators activated

Question 9

T - lymphocytes

Answer 9

Cell mediated - secrete T-cells directly to destroy cells

• Killer T cells: destroy host cells that are infected by foreign invaders (apoptosis)
• Helper T cells: enhance B cell production of antibodies
• Suppressor T cells: regulates/balances B cell antibody production and suppressor T cell production

Question 10

Clonal Selection

Answer 10

B & T cells produce specific antigens that divide and replicate
Important concept in innate immunity

Question 11

Primary Response

Answer 11

Slower response time
Neutralization: hinder a toxic antigen = harmless to other cells
Apoptosis: programed death of cells during phagocytosis

Question 12

Secondary Response

Answer 12

Faster response time

Memory B cells are produced allowing a faster response the next time the same antigen is displaced

Question 13

Vaccinations

Answer 13

stimulate antibody production against specific pathogen

Question 14

Adaptive Immunity Stages

Answer 14

Recognition of antigen
Activation of lymphocytes (clonal/differentiation)
Effector phase (immune attack/elimination of antigens)
Decline of antigens > lymphocyte death (apoptosis)
Memory cells remain for later response (secondary)

Question 14

Cytokines

Answer 14

Chemicals released by both B & T lymphocytes

Question 15

T cell regulators (2)

Answer 15

Helper T cells & Effector T cells (cytoxic)