GRCC BI 122 LYMPHATIC SYSTEM EXAM 2025

What are the functions of the lymphatic system? - - 1. Immunity - Transport of white blood cells - Transport of pathogens to lymph nodes - Production of antibodies 2. Interstitial Fluid Return 3. Transport fat from small intestine to veins What is the hierarchy of the lymphatic system? - - 1. Capillaries 2. Lymph vessels 3. Lymph nodes 4. Lymph vessels 5. Lymph trunk 6. Lymph duct 7. Subclavian veins What is the function and characteristics of the capillaries ? - -1. Collect interstitial fluid (lymph) 2. They have similar anatomy as blood capillaries 3. Closed ends 4. Same distance as blood capillaries What are some characteristics of lymphatic vessels ? - -1. Same tunic anatomy as veins 2. Contains semi-lunar valves 3. Periodic lymph nodes What is the function of lymphatic trunks? - -Collect lymph from Lymph vessels What is the function and characteristic of Lymph ducts ? - -1. Collect lymph from lymph trunks 2. both ducts (thoracic and right lymphatic) dump into subclavian veins Where can you find lymphatic capillaries ? - -Dermis. Any break in dermis allows entry into lymphatic system e.g. bee stings, spider bites What is the function of lymph nodes ? - -Destroy pathogens GRCC GRCC What are some characteristics of lymph nodes ? - -1. Serves as house for increasing number of dividing and mature lymphocytes and macrophages 2. Located along lymphatic pathways Where else are lymphocytes produced? - -Red marrow What nodes are affected with a throat or respiratory infection ? - -Cervical nodes become enlarged producing swollen glands What are the first nodes in line to drain a tumor ? - -Sentinesl lymph nodes should be the first to receive cells from a metastasizing cancer What is Elephantiasis ? - -Obstruction of the lymph nodes, caused by, nematodes worms, tumors or infection, and result in, tissue edema and collagen fiber formation How is lymph formed ? - -Blood capillary filtration pushes plasma into interstitial spaces and then into lymph capillaries Lymph flow occurs via ? - -1. Skeletal muscle contraction in limbs 2. Contraction of respiratory muscles and abdominal viscera 3. Smooth muscle contraction in larger lymph vessels and trunks How can edema occur ? - -When interstitial fluid accumulation exceeds its movement into lymphatic capillaries What are the six organs of the lymphatic system ? - -1. Lymph nodes 2. Thymus 3. Spleen 4. Tonsils 5. Peyer's patches ( Aggregated lymphatic nodules) 6. Appendix What is the function of the thymus ? - -Maturation of T lymphocytes from red marrow. Shrinks post-puberty then replace by connective tissue in elderly What is the function of the spleen? - -1. Filters blood same way lymph nodes filter lymph by destroying: - Old red blood cells via capillary channels - cellular debris via macrophages - Pathogens via lymphocytes and macrophages 2. Hemopoesis (Red blood cell production) in fetus 3. Blood storage - similar structure as lymph nodes What are tonsils ? What is their function ? - -Unencapsulated lymph tissue. It gathers and remove inhaled and ingested pathogens. GRCC GRCC What is the mechanism by which tonsils destroy pathogens ? - -Bacteria are invited into crypts and then attacked by dense concentrations of lymphocytes. Why would our bodies take the risk to invite bacteria into the body? - -To make antibodies and be prepared for future attacks What is tonsillitis? - -Inflammation of the tonsils (usually palatine). Bacteria is the normal pathogen Where are Peyer's patches located and what is their function? - -Located in ileum. they gather and remove ingested pathogens. What is the function of the appendix ? - -Gather and remove ingested pathogens. What is appendicitis? - -Any inflammation of the appendix usually resulting from bacterial infection. What are the two kinds of lymphatic response to pathogens? - -- Nonspecific defense: Defense mechanism is the same regardless of type of pathogen. e.g. phagocytosis, fever, inflammation - Specific defense: Defense is directed to a specific antigen. e.g. Blood antigens, immunization What are the six types of non-specific defenses ? - -- Species resistant - Mechanical barriers - Chemical barriers - Fever - Inflammation -Phagocytosis How does species resistant work ? - -Entire species is resistant to a group of pathogens e.g. humans and bovine tuberculosis or heart worm. How can alteration of species resistance occur ? - -By the evolution of new pathogen variants e.g. avian flu What are the two types of mechanical barriers and how do they work? - -- Intergument: hard to penetrate and sloughs off carrying pathogens. - Mucous membranes: carries pathogens in mucous to digestive system What are the four types of chemical barriers or complement proteins ? - -- Interferons - Defensins - Collectins - Miscellaneous chemicals How are interferons produced and what its their function? - -Produced by virus. GRCC GRCC Infected cells that interfere with replication of virus in other cells. Increases phagocytosis and decreases tumor growth. What are the three types of interferons ? - -Three types of interferons: -Alpha: secreted by infected cells - Beta: secreted by fibroblast - Gamma: secreted by T cells How are defensins produced and what is their function? - -Produced by granulocytes. Punch holes in bacteria membranes and cell walls. What is the function of collectins? - -They detect subtle differences in non-self antigens then bind to surface making cell more obvious to phagocytes. What are some examples of miscellaneous chemicals ? - -Hydrochloric acid and pepsin in stomach, salt on skin, antibacterial in tears. What happens during a fever? - -- Lymphocyte secrete cause hypothalamus to raise body temperature. - Increasing temperature cause liver and spleen to retain Fe. - Bacteria and fungi unable to reproduce without Fe. - Increasing temperature, increases phagocytosis - High temperatures denature pathogen proteins How is inflammation produced ? - -Localized swelling, redness and heat initiated by basophils. What is phagocytosis ? - -Removal of cells and debris by phagocytes such as neutrophils, monocytes, and macrophages. - Attracted to chemicals released by damaged tissues - chemotaxix- Where do macrophages arise from? - -They arise from monocytes and fix themselves to tissue and vessels. What is one type of specific defense and how does it work ? - -Resistance to a particular pathogen or its toxin. Results in lymphocytes and macrophages recognizing non-self/ foreign antigens When are antigens inventoried? - -Lymphatic system inventories self-antigens prepartum. - Receptors on lymphocytes recognize antigens. Prep