Lymphatic and respiratory Exam 1 well Explained Answers 2025

Why does a problem with the lymphatic system potentially lead to a problem with the immune system? (3 Pts) the lymphatic and immune system play a role in immunity. when the lymphatic system has a problem like a blockage or damage in the lymph vessels, it impairs circulation of lymphocytes and other immune cells, hindering their ability to reach and respond to infections or other threats. it weakens the immune systems ability to fight against illness and foreign objects. Describe the structural and functional relationship of the vessels of the blood vascular system and the lymphatic system. (3 Pts.) the relationship between vessels of the blood vascular systemic and the lymphatic system is that the blood vascular system is responsible for circulation of blood to transport oxygen, nutrients, and waste while the lymphatic system helps to maintain body balance absorb fats, and support immune function. structurally lymphatic vessels are similar to veins in structure but have thinner walls and more valves. they carry the lymph to lymph nodes where it is then filtered like the blood vascular system does What is the consequence of obstruction of the lymphatics? (2 Pts.) the consequence of obstruction of the lymphatics can lead to swelling because of a lymph fluid buildup in the affected area, an impaired immune function and not being able to transport immune cells or remove waste products, and can cause conditions like lymphedema, or chronic inflammation How does the number of afferent vs. efferent lymphatic vessels differ in a lymph node and how does the difference allow lymphocytes and macrophages to perform their protective function (2 pts)? lymph nodes have more afferent vessels to bring lymph into the node from a wide area, and fewer efferent vessels to allow lymph to leave. this difference helps slow the flow of lymph through the node, which enhances filtration and exposure to lymphocytes and macrophages. this structure enables efficient detection of pathogens and initiate immune responses, and identify possible threats. Why do lymph nodes get swollen when you are sick? (2 Pts.) the reason lymph nodes get swollen when you are sick is because the lymph nodes act as a filter that traps pathogens that have entered lymphatic circulation. when large numbers of pathogens become trapped in a lymph node, they can trigger a response to cause the lymph node to enlarge or swell What are the cellular populations of lymphoid tissue and what purpose do they serve? (6 Pts.) macrophages- mature monocytes that are very active phagocytes b and t lymphocytes- agranulocytes with diverse immune functions, like antibody production, and immune defense dendritic cells- immune cells with spiny processes resembling dendrites of neurons, and are a link between innate and adaptive immune systems reticular cells- abundant in organs like the spleen and lymph nodes, and produce reticular fibers composed of specalized collagen fibers and help immune support and regulation. Name and describe the functions of the other lymphoid organs of the body (other then lymph nodes). (4 Pts.) thymus- the site of development and maturation of T lymphocyes. generates a population of functional T cells capable of protecting the body from pathogens spleen- helps filter blood, and remove old or damaged red blood cells. is a reservoir for immune cells like B and T lymphocytes, macrophages and dedritic cells. it contains white pulp and filters pathogens from blood mucosa-associated lymphoid tissue (MALT)- helps protect mucosal surfaces from pathogens and initiates immune responses directly at the site of antigen entry into the body, and produces local immune responses bone marrow- the primary lymphoid organ responsible for the production of red blood cells, and lymphocytes. B cells mature in bone marrow while T cell precursors are generated here before migrating to the thymus for maturation When you cut your finger, which line of defense is compromised? Why do we cover a wound with a bandage? (2 Pts.) when you cut your finger, you have compromised your first line of defense known as innate immunity, which includes surface barriers like cutaneous membrane. the reason we cover the wound with a bandage is because it temporarily takes the place of the breached surface barrier and acts to help prevent the entry of pathogens into the body What are the signs of inflammation? What are several inflammatory chemicals and what roles do they serve? How does inflammation serve as a protective function (beneficial effects)? (6 Pts.)? the signs of inflammation include redness, heat, swelling and pain. several inflammatory chemicals include: histamines- help induce vasodilation which relax and smooth the muscle supplying damages tissues, and increases permability to local capillaries prostaglandins- trigger action potentials in peripheral processes of sensory neurons, letting us know were in pain inflammation serves as a protective function because it helps prevent the spread of damage and disposes of debris and pathogens, while alerting the adaptive immune system and sets up repair What often causes “flu-like” symptoms when one is infected with a pathogen? (2 Pts.) many cytokines, and innterferons to a lesser extent induce a "flu like" symptom, which includes fever chills and aches due in part to stimulation of inflammation What causes a fever? (2 Pts.) a fever is caused by an initiation of chemicals called pyrogens, which are released from damaged cells or certain kinds of bacteria. pyrogens act on the hypothalamus causing the hypothalamic thermostat to reset to a higher range Your classmate insists that since your patient has a fever, she must have an infection because the elevated temperature of fever kills the bacteria. Explain to your classmate why this is wrong. (2 Pts) a body temperature high enough to kill bacterial cells would probably end up killing most of the body's cells too if that were the case. a fever can occur independently of a bacterial infection, and a fever's more likely contribution is that phagocytes function more effciently at a slightly higher body temperature List and explain the 4 steps of phagocytic mobilization, when leukocytosis-inducing factors are released by injured cells at an inflamed site. ( 4 pts) 1.) leukocytosis- neutrophils are released from the bone marrow in response to leukocytosis, including factors released by injured cells 2.) margination- inflammatory mediators and activated complement proteins attract neutrophils and enable them to leave blood and enter tissue; make capillary endothelium in damaged areas "sticky" and neutrophils adhere to the capillary wall 3.) diapedesis- inflammatory mediators increase capillary permability; provide space between endothelial cells for neutrophils to squeeze through into damaged tissue; destroy bacteria and other debris 4.) chemotaxis- inflammatory chemicals attract neutrophils to the injury site Name the body’s antimicrobial substances and describe their function. (4 Pts.) interferons- cytokines produced by macrophages, dendritic cells, NK cells and cells of adaptive immunity; produced in response to infection wiht intracellular agents such as viruses or intracellular bacteria; primary action is to inhibit viral replication inside host cells complement- triggers release of inflammatory mediators from cells such as basophils and mast cells, and act as inflammatory mediators themselves What is adaptive immunity? What are the components of the adaptive immune system and what function does each serve? (5 Pts.) uses lymphocytes, APC's and specific molecules to identify and destroy nonself substances. depends upon the ability of its cells to recongize antigens by binding to the or communicate with one another so that the whole system mounts a specific response What is a T cell clone? How is each T cell clone genetically unique? Which clones are destroyed in the thymus, and why? (2 Pts) a T cell clone is a population of T cells that can respond to a specific antigen. all the cells of this clone have a unique T cell receptor that binds to a specific antigenic determinant. the thymus destorys clones that cannot recognize antigens as well as self-reactive T cells which would attack the body's own cells Why are both class I and class II MHC molecules needed? (3 Pts) class I MHC- endogenous and let you know whats going on inside the cell. cytotoxic T cells will recognize these molecules class II MHC- exogenous molecules on B cells and other antigen presenting cells. they are wearing the skins of their enemies, and both are needed to one being exogenous and the others being endogenous Although the adaptive immune system has two arms, it has been said, "no T helper cells, no immunity." Why does so much of the immune system malfunction if TH cells are not working properly?. (2 Pts.) helper T cells serve as the relay center. they are given the info from the "daily runs: of other cells, like what pathogens they saw, etc. Helper T cells then tell the rest what they need to do, and if they need to attack or not amongst other things. without helper T cells the other cells won't have orders to carry out. kind of like the general commanding soldiers. Where do B cells mature? Why do only about 10% of the cells complete their maturation process? (3 Pts.) B cells mature in bone marrow, and approximately 90% of B cells do not complete their maturation process because they fail to pass the stringent selection criteria for self-reactivity ensuring that mature B cells recognize and respond to foreign antigens while avoiding harmful reactions against the body's own tissues How do plasma cells and memory B cells differ? (2 Pts) plasma cells confer immediate protection by the secretion of specific antibodies, and memory B cells confer rapid and enhanced response to secondary exposure List the 5 classes of antibodies and the function of each ( 5 pts). igG: monomer that is most abundant and diverse antibody in primary and secondary response; crosses the placenta and confers passive immunity igA: dimer that helps prevent attachment of pathogens to epithelial cell surfaces igM: penatomer released by plasma cells during the primary immune response igE: monomer that binds to mast cells and basophils causing histamine release when activated igD: monomer attached to the surface of B cells, important in B cell activation What are the mechanisms of antibody action and what are the results of these actions? (6 Pts.) mechanisms of antibody action: antibodies may inhibit infection by preventing the antigen from binding to its target, tagging a pathogen for destruction by macrophages or neutrophils or activating the complement cascade. neutralization, agglutination, precipitation, and complement fixation and activation What is the antigen challenge, and where does it usually take place? (4 Pts.) the antigen chall