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18.8: Key Terms

  • Page ID
    69320
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    Example and Directions
    Words (or words that have the same definition)The definition is case sensitive(Optional) Image to display with the definition [Not displayed in Glossary, only in pop-up on pages](Optional) Caption for Image(Optional) External or Internal Link(Optional) Source for Definition
    (Eg. "Genetic, Hereditary, DNA ...")(Eg. "Relating to genes or heredity")The infamous double helix https://bio.libretexts.org/CC-BY-SA; Delmar Larsen
    Glossary Entries
    Word(s)DefinitionImageCaptionLinkSource
    ABO blood groupblood-type classification based on the presence or absence of A and B glycoproteins on the erythrocyte membrane surface    
    agglutinationclustering of cells into masses linked by antibodies    
    agranular leukocytesleukocytes with few granules in their cytoplasm; specifically, monocytes, lymphocytes, and NK cells    
    albuminmost abundant plasma protein, accounting for most of the osmotic pressure of plasma    
    anemiadeficiency of red blood cells or hemoglobin    
    antibodies(also, immunoglobulins or gamma globulins) antigen-specific proteins produced by specialized B lymphocytes that protect the body by binding to foreign objects such as bacteria and viruses    
    anticoagulantsubstance such as heparin that opposes coagulation    
    antithrombinanticoagulant that inactivates factor X and opposes the conversion of prothrombin (factor II) into thrombin in the common pathway    
    B lymphocytes(also, B cells) lymphocytes that defend the body against specific pathogens and thereby provide specific immunity    
    basophilsgranulocytes that stain with a basic (alkaline) stain and store histamine and heparin    
    bilirubinyellowish bile pigment produced when iron is removed from heme and is further broken down into waste products    
    biliverdingreen bile pigment produced when the non-iron portion of heme is degraded into a waste product; converted to bilirubin in the liver    
    bloodliquid connective tissue composed of formed elements—erythrocytes, leukocytes, and platelets—and a fluid extracellular matrix called plasma; component of the cardiovascular system    
    bone marrow biopsydiagnostic test of a sample of red bone marrow    
    bone marrow transplanttreatment in which a donor’s healthy bone marrow with its stem cells replaces diseased or damaged bone marrow of a patient    
    bruiselocalized bleeding under the skin due to damaged blood vessels    
    buffy coatthin, pale layer of leukocytes and platelets that separates the erythrocytes from the plasma in a sample of centrifuged blood    
    carbaminohemoglobincompound of carbon dioxide and hemoglobin, and one of the ways in which carbon dioxide is carried in the blood    
    clotting factorsgroup of 12 identified substances active in coagulation    
    coagulationformation of a blood clot; part of the process of hemostasis    
    colony-stimulating factors (CSFs)glycoproteins that trigger the proliferation and differentiation of myeloblasts into granular leukocytes (basophils, neutrophils, and eosinophils)    
    common pathwayfinal coagulation pathway activated either by the intrinsic or the extrinsic pathway, and ending in the formation of a blood clot    
    cross matchingblood test for identification of blood type using antibodies and small samples of blood    
    cytokinesclass of proteins that act as autocrine or paracrine signaling molecules; in the cardiovascular system, they stimulate the proliferation of progenitor cells and help to stimulate both nonspecific and specific resistance to disease    
    defensinsantimicrobial proteins released from neutrophils and macrophages that create openings in the plasma membranes to kill cells    
    deoxyhemoglobinmolecule of hemoglobin without an oxygen molecule bound to it    
    diapedesis(also, emigration) process by which leukocytes squeeze through adjacent cells in a blood vessel wall to enter tissues    
    embolusthrombus that has broken free from the blood vessel wall and entered the circulation    
    emigration(also, diapedesis) process by which leukocytes squeeze through adjacent cells in a blood vessel wall to enter tissues    
    eosinophilsgranulocytes that stain with eosin; they release antihistamines and are especially active against parasitic worms    
    erythrocyte(also, red blood cell) mature myeloid blood cell that is composed mostly of hemoglobin and functions primarily in the transportation of oxygen and carbon dioxide    
    erythropoietin (EPO)glycoprotein that triggers the bone marrow to produce RBCs; secreted by the kidney in response to low oxygen levels    
    extrinsic pathwayinitial coagulation pathway that begins with tissue damage and results in the activation of the common pathway    
    ferritinprotein-containing storage form of iron found in the bone marrow, liver, and spleen    
    fibrininsoluble, filamentous protein that forms the structure of a blood clot    
    fibrinogenplasma protein produced in the liver and involved in blood clotting    
    fibrinolysisgradual degradation of a blood clot    
    formed elementscellular components of blood; that is, erythrocytes, leukocytes, and platelets    
    globinheme-containing globular protein that is a constituent of hemoglobin    
    globulinsheterogeneous group of plasma proteins that includes transport proteins, clotting factors, immune proteins, and others    
    granular leukocytesleukocytes with abundant granules in their cytoplasm; specifically, neutrophils, eosinophils, and basophils    
    hematocrit(also, packed cell volume) volume percentage of erythrocytes in a sample of centrifuged blood    
    hematopoietic stem celltype of pluripotent stem cell that gives rise to the formed elements of blood (hemocytoblast)    
    hemered, iron-containing pigment to which oxygen binds in hemoglobin    
    hemocytoblasthematopoietic stem cell that gives rise to the formed elements of blood    
    hemoglobinoxygen-carrying compound in erythrocytes    
    hemolysisdestruction (lysis) of erythrocytes and the release of their hemoglobin into circulation    
    hemolytic disease of the newborn (HDN)(also, erythroblastosis fetalis) disorder causing agglutination and hemolysis in an Rh+ fetus or newborn of an Rh person    
    hemophiliagenetic disorder characterized by inadequate synthesis of clotting factors    
    hemopoiesisproduction of the formed elements of blood    
    hemopoietic growth factorschemical signals including erythropoietin, thrombopoietin, colony-stimulating factors, and interleukins that regulate the differentiation and proliferation of particular blood progenitor cells    
    hemorrhageexcessive bleeding    
    hemosiderinprotein-containing storage form of iron found in the bone marrow, liver, and spleen    
    hemostasisphysiological process by which bleeding ceases    
    heparinshort-acting anticoagulant stored in mast cells and released when tissues are injured, opposes prothrombin    
    hypoxemiabelow-normal level of oxygen saturation of blood (typically <95 percent)    
    immunoglobulins(also, antibodies or gamma globulins) antigen-specific proteins produced by specialized B lymphocytes that protect the body by binding to foreign objects such as bacteria and viruses    
    interleukinssignaling molecules that may function in hemopoiesis, inflammation, and specific immune responses    
    intrinsic pathwayinitial coagulation pathway that begins with vascular damage or contact with foreign substances, and results in the activation of the common pathway    
    jaundiceyellowing of the skin or whites of the eyes due to excess bilirubin in the blood    
    leukemiacancer involving leukocytes    
    leukocyte(also, white blood cell) colorless, nucleated blood cell, the chief function of which is to protect the body from disease    
    leukocytosisexcessive leukocyte proliferation    
    leukopeniabelow-normal production of leukocytes    
    lymphocytesagranular leukocytes of the lymphoid stem cell line, many of which function in specific immunity    
    lymphoid stem cellstype of hematopoietic stem cells that gives rise to lymphocytes, including various T cells, B cells, and NK cells, all of which function in immunity    
    lymphomaform of cancer in which masses of malignant T and/or B lymphocytes collect in lymph nodes, the spleen, the liver, and other tissues    
    lysozymedigestive enzyme with bactericidal properties    
    macrophagephagocytic cell of the myeloid lineage; a matured monocyte    
    megakaryocytebone marrow cell that produces platelets    
    memory celltype of B or T lymphocyte that forms after exposure to a pathogen    
    monocytesagranular leukocytes of the myeloid stem cell line that circulate in the bloodstream; tissue monocytes are macrophages    
    myeloid stem cellstype of hematopoietic stem cell that gives rise to some formed elements, including erythrocytes, megakaryocytes that produce platelets, and a myeloblast lineage that gives rise to monocytes and three forms of granular leukocytes (neutrophils, eosinophils, and basophils)    
    natural killer (NK) cellscytotoxic lymphocytes capable of recognizing cells that do not express “self” proteins on their plasma membrane or that contain foreign or abnormal markers; provide generalized, nonspecific immunity    
    neutrophilsgranulocytes that stain with a neutral dye and are the most numerous of the leukocytes; especially active against bacteria    
    oxyhemoglobinmolecule of hemoglobin to which oxygen is bound    
    packed cell volume (PCV)(also, hematocrit) volume percentage of erythrocytes present in a sample of centrifuged blood    
    plasmain blood, the liquid extracellular matrix composed mostly of water that circulates the formed elements and dissolved materials throughout the cardiovascular system    
    plasminblood protein active in fibrinolysis    
    platelet plugaccumulation and adhesion of platelets at the site of blood vessel injury    
    platelets(also, thrombocytes) one of the formed elements of blood that consists of cell fragments broken off from megakaryocytes    
    pluripotent stem cellstem cell that derives from totipotent stem cells and is capable of differentiating into many, but not all, cell types    
    polycythemiaelevated level of hemoglobin, whether adaptive or pathological    
    polymorphonuclearhaving a lobed nucleus, as seen in some leukocytes    
    positive chemotaxisprocess in which a cell is attracted to move in the direction of chemical stimuli    
    red blood cells (RBCs)(also, erythrocytes) one of the formed elements of blood that transports oxygen    
    reticulocyteimmature erythrocyte that may still contain fragments of organelles    
    Rh blood groupblood-type classification based on the presence or absence of the antigen Rh on the erythrocyte membrane surface    
    serumblood plasma that does not contain clotting factors    
    sickle cell disease(also, sickle cell anemia) inherited blood disorder in which hemoglobin molecules are malformed, leading to the breakdown of RBCs that take on a characteristic sickle shape    
    T lymphocytes(also, T cells) lymphocytes that provide cellular-level immunity by physically attacking foreign or diseased cells    
    thalassemiainherited blood disorder in which maturation of RBCs does not proceed normally, leading to abnormal formation of hemoglobin and the destruction of RBCs    
    thrombinenzyme essential for the final steps in formation of a fibrin clot    
    thrombocytesplatelets, one of the formed elements of blood that consists of cell fragments broken off from megakaryocytes    
    thrombocytopeniacondition in which there are too few platelets, resulting in abnormal bleeding (hemophilia)    
    thrombocytosiscondition in which there are too many platelets, resulting in abnormal clotting (thrombosis)    
    thrombopoietinhormone secreted by the liver and kidneys that prompts the development of megakaryocytes into thrombocytes (platelets)    
    thrombosisexcessive clot formation    
    thrombusaggregation of fibrin, platelets, and erythrocytes in an intact artery or vein    
    tissue factorprotein thromboplastin, which initiates the extrinsic pathway when released in response to tissue damage    
    totipotent stem cellembryonic stem cell that is capable of differentiating into any and all cells of the body; enabling the full development of an organism    
    transferrinplasma protein that binds reversibly to iron and distributes it throughout the body    
    universal donorindividual with type O blood    
    universal recipientindividual with type AB+ blood    
    vascular spasminitial step in hemostasis, in which the smooth muscle in the walls of the ruptured or damaged blood vessel contracts    
    white blood cells (WBCs)(also, leukocytes) one of the formed elements of blood that provides defense against disease agents and foreign materials    

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