Human Physiology (Biol 236)
Exam Outline

It is to be understood that you will have read the corresponding sections of the textbook for lecture topics that we have covered!
Updated 11/18/19
Chapter 9 Outline (immune Physiology)
• Know primary lymph organs and their immune function (bone marrow and thymus).
• Know secondary lymph organs and their immune function (lymph nodes, lymphatic vessels & blood vessels, tonsils, brain, spleen, intestines, appendix, liver), including - organ-specific macrophages (ex. Kupfer cells in liver, microglia in brain, alveolar macrophages in lungs)

Innate Immunity (or non-specific immunity):
• For innate immunity, what are some external innate defenses and internal innate defenses?
External innate immunity:
- skin is physical barriers to pathogen entry
- stomach acid destroys consumed pathogens
- tonsils, respiratory mucus and cilia, and alveolar macrophages are barriers to inhaled pathogens
- acidic genital tracts
- acidic urethral tracts
- tears are antimicrobial
- sweat is antimicrobial
Internal innate immunity:
- WBC's = neutrophils and monocytes in bloodstream, (monocytes can extravasate into tissues as macrophages)
- WBC's secrete endogenous pyrogens to increase your body temp (fever), which can kill bacteria, secrete chemical cries for help (cytokines & chemokines)
- macrophages can destroy pathogens in tissues, become APC.
- secrete chemical cry for help (cytokines and chemokines) to attract other immune cells to come help.
- mast cells secrete histamine to cause inflammation (makes blood vessels dilate and become "leaky" to allow WBC's out of blood stream into tissues).
- complement proteins cause inflammation and kill bacterial cells by poking holes in them so they burst.
- natural killer cells destroy tumor cells with toxic granules, and secrete interferons to kill viral cells.

Adaptive Immunity (or specific immunity, or humoral immunity):
• The 2 types of Adapative Immunity:
- Cell-mediated = is all about T-cells! No antibodies needed. Activated helper T-cells then activate cytotoxic T-cells, memory T-cells, and also activate B-cells to make antibodies. T regulatory cells are also important.
- Antibody-mediated = is all about B-cells, which make antibodies. Antibodies will target specific antigens on pathogenic cells and cause agglutination reaction, attracting phagocytic cells to destroy the pathogen. B-cells, once exposed to an antigen, will clone themselves to make more Plama B-cells (can fight now) and Memory B-cells (will fight later).

• Regarding T-lymphocytes (T-cells), what is the difference between helper T-cells, cytotoxic T-cells, regulatory T-cell, and memory T-cells?

• What is the difference between Primary immune response and Secondary immune response in terms of protection from pathogens by relative number of B-cells?

• What is the general sequence of events that occur with activation of innate immunity to formation of adaptive immunity once a pathogen has entered the body? (See flow diagram)
- neutrophils are first on scene in bloodstream, followed by monocytes.
- Monocytes can extravasate out of bloodstream and enter tissues as macrophages.
- Macrophages encounter pathogenic cells and destroy directly, but move a pathogen's antigen to it's cell surface. Now the macrophage becomes an APC.
- APC presents the antigen to a Helper T-cell, and the Helper T-cell becomes activated.
- Activated T-cell can then activate other T-cells (cytotoxic T-cells and memory T-cells) as well as activate B-cells into making antibodies specific to the antigen.
- When B-cell with antibodies encounters the antigen on the pathogen, it will release antibodies to bind to pathogens, & cause agglutination reaction, and also it will cause clonal replication of more B-cells: plasma B-cells that can fight now, and memory B-cells that will wait to fight later.

Regarding classification of immunity:
• Under Active Immunity, what is the difference between natural active versus artificial active immunity?
• Under Passive Immunity, what is the difference between natural passive versus artifical passive immunity?
• What is herd immunity?
• What are some autoimmune disorders covered?

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