Lymphatic System
Anatomy Lymphatic vessels: meet up in capillaries of of tissues to collect extra water, and have an end point of meeting up with lymphatic ducts that empty fluid into large veins in the chest and neck. Lymph: Tissue fluid that enters a lymphatic capillary (clear fluid that surrounds new piercings!) Lymphatic capillaries move lymph larger lymphatic vessels and into lymph nodes. Large vessels have valves that keep lymph flowing in one direction.
Anatomy Lymph nodes: Encapsulated structures that are round, oval, or bean shaped. Range from the size of a pin to about an inch wide Function: Filter the lymph and destroy any microorganisms or cancerous cells that are present. Grouped together in chains where there is high risk of invasion of microorganisms and cancerous cells.
Anatomy Lymphoid tissues: contain leukocytes, lymphocytes, and macrophages that are active in the immune system's response. Tonsils Adenoids Peyer s patches - in intestines Appendix
Anatomy Lymphoid organs: Thymus and the Spleen Thymus: Secretes hormones and produces T-Cells Spleen: removes and recycles old erythrocytes in the blood. Also is a place of storage for whole blood.
Physiology of the Immune Response Immune response = blood and the lymphatic system working to destroy microorganisms + cancerous cells Immune system begins with detection of microorganisms Yeast, Fungi, Bacteria, Viruses, Protozoa, etc. Microorganisms that cause disease = PATHOGENS Pathogen detected = ATTACK!!!
Physiology of the Immune Response Neutrophils - Engulf and destroy bacteria that are coated with antibodies Eosinophils - Release chemicals that destroy foreign cells and kill parasites Foreign cells = Pollen, animal dander, dust Basophils - Release histamine at the site of tissue injury Histamine dilates blood vessels + blood flow = redness + more WBC move to the area
Physiology of the Immune Response - Lymphocytes NK Cells (Natural Killer Cells) - Recognize cancer cell or cell infected with a virus, and release chemicals to destroy it Recognize cells before before coated with antibodies B cells - Inactive until monocyte presents them with fragments from raten pathogen B cell changes into plasma cell and produces antibodies to coat pathogen Activate helper T cells
Physiology of the Immune Response - Lymphocytes T cells - 4 subsets; matured in the thymus Cytotoxic T cells - produce toxic granules to kill cells infected with virus Helper T cells - produce interleukin and stimulate the production of cytotoxic T cells Interleukin = proteins mediate communication between cells regulate cell growth, differentiation, and motility stimulating immune responses Ex: Inflammation Produce memory T cells
Physiology of the Immune Response - Lymphocytes Memory T cells - Created when a helper T cell is exposed to a virus. Inactive until the next time that virus enters the body Remember the virus and become cytotoxic T cells Suppressor T cells - Limit the extent and duration of the immune response by inhibiting B cells and Cytotoxic T cells.
Physiology of the Immune Response - Monocytes Jobs of the Monocyte: Engulf and destroy pathogens coated with antibodies Eat dead leukocytes and cellular debris Take fragments of pathogens and present them to B and T cell lymphocytes Produce: Interferon -stimulates other cells to produce an antiviral substance that prevents a virus from entering them and reproducing itself stops spread of viral infection Tumor necrosis factor - Destroys endotoxins produced by certain bacteria. Destroys certain cancer cells. Interleukin
Physiology of the Immune Response Antibodies - Coat the outside of a bacterium or a virus and mark it to be destroyed. Coating attracts phagocytes to come and eat the bacterium/virus AKA - IMMUNOGLOBULINS
Physiology of the Immune Response - Complement Proteins Complement proteins - group of 9 proteins that activate each other Antibodies coat a bacterium/virus complement proteins attach to antibodies to complement their effect and drill holes into the bacterium/virus.