Immunity & Lymphatic Flashcards
describe the major functions of the lymphatic system
the lymphatic system is a group of organs and tissues that not only works with the immune system but also participates in number of functions such as fluid homeostasis; regulation of interstitial fluid volume, absorption of dietary fats, and immune functions
identify the differences between innate and adaptive immunity and the 3 lines of defense
innate (nonspecific) immunity responds to all pathogens in the SAME way – born with (genetic); adaptive (specific) immunity respond individually to unique antigens and have to be exposed to specific antigen for response to be initiated but once mount response occurs then it becomes a dominant response to whenever that antigen is present again – cell-mediated and antibody-mediated; first line acts as surface barriers within cutaneous and mucous membranes to block entry of pathogens into body; second line makeup innate immunity; third line makeup adaptive immunity
describe the structure and function of the lymphoid organs
tonsils - trap bacteria and debris (pharyngeal, palatine, and lingual)
thymus - does not trap pathogens; secretes hormones that enable it to generate population of functional T cells capable of protecting body from pathogens
lymph nodes - limit spread of pathogens through body by acting as filters; trap pathogens and prevent them from traveling elsewhere (cervical, axillary, mesenteric, and inguinal)
spleen - largest lymphoid organ; contain macrophages that destroy old erythrocytes (red pulp) and filters pathogens from blood & contain leukocytes and dendritic cells (white pulp)
MALT - protects mucous membranes which are exposed to a large number of pathogens; protect oral and nasal cavities
describe the differences between antibody-mediated (humoral) and cell-mediated immunity
cell-mediated is brought about by two types of T cells; antibody-mediated is carried out by B cells and proteins they produce (antibodies)
describe the cells and proteins that make up the immune system
agranulocytes - lack cytoplasmic granules (B and T lymphocytes & monocytes)
granulocytes - contain cytoplasmic granules (neutrophils, eosinophils, and basophils)
phagocytes - “eat” foreign or damaged cells (neutrophils and macrophages)
natural killer cells - located in blood & spleen and function primarily in innate immunity
dendritic cells - located in many lymphoid organs and part of innate immunity, but main role is to activate T cells of adaptive immunity
antibodies - proteins produced by B lymphocytes and function in adaptive immunity
complement system - functions in innate immunity
cytokines - diverse group of proteins secreted by cells of both innate and adaptive immunity; regulate development and activity of immune cells
explain how the immune and lymphatic systems are structurally and functionally connected
immune and lymphatic systems function together in immunity; they both protect the body from both cellular injury and disease-causing cells and pathogens
lymphoid organs and tissues provide residence for cells of immune system; lymphoid organs and tissues trap pathogens for immune system; lymphoid organs activate cells of immune system
describe the components of the inflammatory response
inflammatory response is a nonspecific response to cellular injury; several complement proteins enhance this response by triggering basophils and mast cells to release chemicals that mediate inflammation
part 1: tissue damage occurs – damaged cells and mast cells release inflammatory mediators – inflammatory mediators trigger vasodilation of arterioles, increased capillary permeability, occurrence of pain, recruitment of other cells (chemotaxis)
part 2: local macrophages activated – neutrophils migrate by chemotaxis to the damaged tissue and phagocytize bacteria and cellular debris – monocytes migrate to the tissue by chemotaxis and become macrophages, which phagocytize pathogens and cellular debris – the bone marrow increases production of leukocytes, leading to leukocytosis
inflammatory mediators (histamine, serotonin), basophils, and complement proteins
cardinal signs of inflammation: redness (rubor), heat (calor), swelling (tumor)(edema), and pain (dolor)
distinguish between antigens and antibodies
antigen - substance that B or T cells recognize
antibody - proteins secreted by B cells
describe the types of B and T lymphocytes
B cells - produce antibodies that are used to attack invading bacteria, viruses, and toxins
T cells - destroy the body’s own cells that have themselves been taken over by viruses or become cancerous (helper, cytotoxic, and memory)
identify the 5 basic classes of antibody
IgG - most prevalent antibody; consists of single subunit; only antibody able to cross from blood of pregnant woman to her developing fetus through placenta
IgA - usually dimer; consisting of two Y-shaped subunits; gives antibody 4 antigen-binding sites; present in secretions from skin, mucous membranes, and exocrine glands
IgM - largest antibody; pentamer, which consists of 5 subunits in starlike arrangement for total of 10 antigen-binding sites; generally first antibody secreted by plasma cells when body is invaded by pathogen; also exists as single subunit embedded in B cell plasma membrane where it functions as B cell receptor
IgE - single-subunit antibody; generally present in very low amounts in body’s fluids; binds to antigens associated with parasitic pathogens and environmental antigens
IgD - unique because it is the only antibody not secreted by B cells in significant amounts; single subunit located on surface of B cells; acts as an antigen receptor which helps activate B cells in similar manner to IgM
discuss the rational for vaccinations and relate it to immunological memory
adaptive immunity has capacity for immunological memory – exposure to antigen is “remembered” by specific lymphocytes and antibodies which allows more rapid and efficient response on subsequent exposures
vaccination involves exposing individual to antigen to elicit primary immune response and generate memory cells; then if individual is exposed to antigen again, secondary immune response will occur and symptoms will be minimal
define immunodeficiency and autoimmune disorders
immunodeficiency disorders - occur when one or more components of immune system fail
autoimmune disorders - immune system may treat self antigens as foreign and attack body’s own tissues
identify the 4 types of hypersensitivity disorders
type 1: immediate - most common; allergies
type 2: antibody-mediated - antibodies produced by immune response to foreign antigens also bind to self antigens
type 3: immune complex-mediated - reactions are mediated by immune complexes or clusters of soluble antigens bound to antibodies
type 4: delayed-type - unique in that it is mediated by T cells rather than antibodies
