Division of Biology
General Biology Down by the river...
Dr. Patricia Cox, Coordinator
Telephone: 974-6225
E-mail: pcox@utk.edu
Biology 101
Outline for Chapter 25: The Nervous, Endocrine and Immune System
I. Defending the body from Invaders
A. Non-specific defenses; target all invaders indiscriminately
B. Specific defenses; directed at specific pathogens. Immunity, antigens
II. Nonspecific defenses of the Immune System
A. Types of nonspecific defenses
1. Physical barriers
a. epithelium
b. glandular secretions and enzymes
c. lining of the stomach
2. Phagocytes
a. microphages
b. macrophages
3. Natural killer cells
4. Interferons
5. Complement proteins
a. can lyse invaders
b. attracts more macrophages to the scene
c. attaches to the invader and acts as a red flag so macrophages can more easily find it.
6. Inflammatory response—histamines (red, warm, swollen)
7. fever
A. Specific resistance is directed toward specific foreign substances and pathogens. It takes 2 forms
1. Innate immunity—inherited
2. Acquired immunity
a. passively acquired immunity
i. acquired as a fetus from mom
ii. acquired from injections
b. actively acquired immunity
i. naturally exposed to antigens in nature
ii. vaccinations
B. Cells involved in the immune response
1. B-lymphocytes (B-cells). Produced in the bone marrow and mature in the bone marrow. Produces antibodies.-involved in Antibody-mediated immunity
a. 3 ways to disable the antigen
i. coat foreign objects and cause them to clump together
ii. combine with them in a way to inhibit some vital function
iii may be involved with the complement system.
b. 5 major classes of antibodies.
2. T-lymphocytes (t-cells)…produced in the bone marrow and matures in the thymus. T-cells do not produce antibodies, they attack other cells that are infected by antigens…4 types
a, helper t-cells (commander –in-chief)
b. cytotoxic t-cells (killer t-cells)
c. suppressor t-cells
d. memory t-cells
A. Antibody-mediated immune response
1, Antbodies produced by b-cells
2. plasma cells
3. memory b-cells
V. Cell-Mediated Immune response –intracellular response.
A. Steps of the cell-mediated response
1. antigen infects the cell..changes properties of the cell membrane
2. macrophages recognize this, engulf infected cell, destroy it but incorporates the antigen onto their membrane
3. This acts as a signal to the helper t-cells that recognize that specific antigen, causing them to secrete interleukins
4. The interleukin activates more helper t-cells
5. These help t-cells travel to the lymph nodes and stimulate the production of cytotoxic t-cells for that antigen
6. Cytotoxic t-cells attack and kill the infected cell
7. Suppressor t-cells shuts the cytotoxic cells down after the infection is under control
8. memory t-cells are formed
VI. Allergies and Autoimmune Disorders
A. Autoimmune diseases
B. Allergies
1. allergen
2. antihistamines
VII. AIDS