Chapter 8 provides knowledge of lymphatic & immune system. The following will be discussed in this chapter: Lymphatic system, nonspecific defenses, specific defenses, induced immunity, immunity side effects. | Chapter 8 Biology 25: Human Biology Prof. Gonsalves Los Angeles City College Loosely Based on Mader’s Human Biology,7th edition Introduction Resistance: Ability to ward off disease. Nonspecific Resistance: Defenses that protect against all pathogens. Specific Resistance: Protection against specific pathogens. Susceptibility: Vulnerability or lack of resistance. Protection Against Invading Pathogens 1. First Line of Defense: Non-specific natural barriers which restrict entry of pathogen. Examples: Skin and mucous membranes. 2. Second Line of Defense: Non-specific defenses that provide rapid local response to pathogen after it has entered body. Examples: Fever, phagocytes (macrophages and neutrophils), inflammation, and interferon. 3. Third line of defense: Antigen-specific immune responses, specifically target and attack invaders that get past first two lines of defense. Examples: Antibodies and lymphocytes. Defenses Against Infection First Line of Defense: Skin is an Effective Barrier Against Infection by Most Pathogens Second Line of Defense: Interferon is Nonspecific Inhibitor of Viral Infection Inflammation is a Nonspecific Defense 1. Damaged cells release chemical signals: Histamine and other molecules. 2. Local response to chemical signals: Increase in local blood flow and vascular permeability Redness Heat Swelling Pain 3. Phagocytic white blood cells come into area: Engulf bacteria, dead cell parts, and other microbes. 4. Tissue heals 14 12 Nonspecific Immunity Distinguish between the kinds of carbohydrates that are produced by mammalian cells and those produced by bacteria. Bacterial carbohydrates flag the cell for phagocytic attack. 3 major groups of phagocytic cells: Neutrophils: 1st to arrive at infection. Mononuclear phagocyte system: Macrophages and monocytes. Organ-specific phagocytes. Inflammatory Response: Nonspecific Defenses Phagocytosis Neutrophils and monocytes are able to squeeze through tiny gaps between adjacent endothelial cells. . | Chapter 8 Biology 25: Human Biology Prof. Gonsalves Los Angeles City College Loosely Based on Mader’s Human Biology,7th edition Introduction Resistance: Ability to ward off disease. Nonspecific Resistance: Defenses that protect against all pathogens. Specific Resistance: Protection against specific pathogens. Susceptibility: Vulnerability or lack of resistance. Protection Against Invading Pathogens 1. First Line of Defense: Non-specific natural barriers which restrict entry of pathogen. Examples: Skin and mucous membranes. 2. Second Line of Defense: Non-specific defenses that provide rapid local response to pathogen after it has entered body. Examples: Fever, phagocytes (macrophages and neutrophils), inflammation, and interferon. 3. Third line of defense: Antigen-specific immune responses, specifically target and attack invaders that get past first two lines of defense. Examples: Antibodies and lymphocytes. Defenses Against Infection First Line of Defense: Skin is an Effective Barrier
