NU Lipa Lymphatic System Notes PDF

LYMPHATIC SYSTEM LYMPHATIC SYSTEM Important for the protection of body Functions: 1. Fluid balance- 3 Liters remain in the lymphatic capillaries (lymph) 2. Lipid absorption- (reason why lymph is white in color) 3. Defense- fights infections ANATOMY OF THE LYMPHATIC SYSTEM LYMPHATIC ORGAN...

LYMPHATIC SYSTEM LYMPHATIC SYSTEM Important for the protection of body Functions: 1. Fluid balance- 3 Liters remain in the lymphatic capillaries (lymph) 2. Lipid absorption- (reason why lymph is white in color) 3. Defense- fights infections ANATOMY OF THE LYMPHATIC SYSTEM LYMPHATIC ORGANS Include the tonsils, lymph nodes, spleen and thymus Tonsils - form a protective ring of lymphatic tissue around nasal, oral and pharynx -serves as the protection from nose and mouth -responsible for cleaning/screening of the food we eat Three Kinds of Tonsils 1. Palatine - posterior opening of Oral Cavity, aka. True Tonsils 2. Pharyngeal - internal opening of Nasal Cavity -when enlarged- now called: ADENOID (interfere with normal breathing) 3. Lingual -Posterior surface of the Tongue -Less infected, more difficult to remove Lymph Nodes -rounded in shape, vary in size from small see to shelled almond -Distributed along lymphatic vessels Function: Remove bacteria and tumor cells by producing lymphocytes 3 superficial lymph nodes a. Inguinal nodes of the groin b. Axillary nodes in the armpit c. Cervical nodes in the neck SPLEEN Approx same size with clenched fist Located at the superior corner of abdominal cavity Has 2 specialized lymphatic tissue 1. White pulp- surrounds the arteries in spleen -for production of lymphocytes 2. Red pulp- surrounds the veins -for phagocytizing any immature, old or dead blood cells FUNCTIONS OF SPLEEN Filters blood Act as reservoir (during hemorrhage) Activation of immune response THYMUS Bi-lobed gland, triangular in shaped Site for maturation of T cells Location: in between the lungs Site for lymphocytes and its maturation It becomes very small at the age of 40 years and disappears at 60 years 2 TYPES OF LYMPHOCYTES B CELLS- T CELLS- OVERVIEW OF LYMPHATIC SYSTEM OVERVIEW OF LYMPHATIC SYSTEM cont. IMMUNITY -is the ability to resist damage from pathogens, such as microbes, harmful chemicals and internal threats such as cancer cells. 2 Systems of Immunity 1. Innate Immunity (nonspecific resistance) 2. Adaptive Immunity (specific immunity) Innate immunity- where body recognizes and destroys pathogens but the response to them is the same each time the body is exposed. Adaptive immunity- body recognizes but responses improve each time the pathogen is encountered. Characteristics of Adaptive Immunity 1. Specificity- ability to recognize a substance 2. Memory- ability to remember previous encounter INNATE IMMUNITY Physical Barriers- prevent pathogens from entering -skin, mucous membrane, skin, tears and urine Chemical Mediators -molecules responsible for innate immunity -Lysozyme in tears and saliva- kills bacteria -mucus- prevents entry -histamine, prostaglandins ang leukotriene- increase vasodilation, promote inflammation by causing vasodilation  Interferons -protection against viral infection -do not protect cell that produce them; neighboring cells and immune cells WHITE BLOOD CELLS Most important cellular components of immunity Origin: Red Bone Marrow and lymphatic tissue Natural Killer Cells -15% lymphocyte -recognize classes of cells in general -does not exhibit memory response -part of innate immunity INFLAMMATION Local Inflammation- response confined to a specific area of the body. Symptoms include: redness, heat, swelling, pain Systemic inflammation: response that is distributed throughout the body 3 additions symptoms aside from Local inflammation symptoms: 1 reb bone marrow produces large numbers of neutrophils 2. Pyrogen (fever producing chemical)-heat production to promote activities of immune system and inhibits growth of some microbes. 3. Vascular permeability increase that large amounts of fluid are lost from the blood ADAPTIVE IMMUNITY Can recognize, respond to and remember a particular substance. Antigens- stimulate adaptive immune response (Foreign-pollen dust, foods and drugs; and self- tumor) ANTIBODY-MEDIATED IMMUNITY Involves production of antibodies in response to extracellular antigens. Exposure of the body to an antigen can lead to activation of B cells and production of antibodies, which are responsible for destroying an antigen. Antibodies are sometimes called gamma globulins or immunoglobulins (Ig) because they are globulin proteins involves in immunity. CELL-MEDIATED IMMUNITY Function of cytotoxic T cells and is most effective against microbes that live inside body cells (viruses and bacteria) Involved with some allergic reactions, control of tumor and graft rejection Fights viral infection by destroying virally infected cell reducing the chance that virus can spread to other cells of the body. Cytotoxic T Cells- distinguish virally infected cells from not Helper T Cells- activates T Cell ACQUIRED ADAPTIVE IMMUNITY Not necessarily present at birth  Active Immunity- result when and individual is exposed to an antigen and the response of his immune system is the cause of immunity. (refers to natural exposure, part of daily living) Passive Immunity- occurs when another person or animal develops immunity and immunity is transferred to nonimmune individual. (also called as immunization) 1. Active Natural Immunity- natural exposure to antigen -exposure to virus at an early age 2. Active Artificial Immunity- an antigen is introduced into person’s body to stimulate immune system (vaccination) 3. Passive Natural Immunity- when mother transfers antibodies to child via placenta/mother’s milk 4. Passive Artificial Immunity-usually begins with vaccinating an animal (horse) then pass to human requiring immunity or transferring antibodies from another person to person who needs an immunity. (SERUM)