Porth's Essentials of Pathophysiology, 4e

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Glossary

Glycolysis  A series of enzymatically catalyzed reac- tions, occurring within cells, by which glucose is converted to adenosine triphosphate (ATP) and pyruvic acid during aerobic metabolism. Gonad  A gamete-producing gland, as an ovary or a testis. Gradient  The rate of increase or decrease of a measur- able phenomenon expressed as a function of a sec- ond; or the visual representation of such a change. Granuloma  A small mass of nodular granulation tissue resulting from chronic inflammation, injury, or infection. (Adjective: granulomatous) Hapten  A small, nonproteinaceous substance that is not antigenic by itself but that can act as an antigen when combined with a larger molecule. Haustrum  A structure resembling a recess or saccula- tion. (Plural: haustra) Hematoma  A localized collection of extravasated blood trapped in an organ, space, or tissue, resulting from a break in the wall of a blood vessel. Hematopoiesis  The normal formation and development of blood cells. Hemianopia  Defective vision or blindness in half of the visual field of one or both eyes. Heterogeneous  Consisting of or composed of dissimilar elements or parts; or not having a uniform quality throughout. (Noun: heterogeneity) Heterophagy  The taking into the cell of an exogenous substance by phagocytosis or pinocytosis and the subsequent digestion of the newly formed vacuole by a lysosome. Heterozygous  Having two different alleles at corre- sponding loci on homologous chromosomes. Histology  The branch of anatomy that deals with the minute (microscopic) structure, composition, and function of cells and tissue. (Adjective: histologic) Homolog  Any organ or part corresponding in function, position, origin, and structure to another organ or part, as the flippers of a seal correspond to human hands. (Adjective: homologous) Homozygous  Having two identical alleles at corre- sponding loci on homologous chromosomes. Humoral  Relating to elements dissolved in the blood or body fluids. Hybridoma  A tumor of hybrid cells produced by fusion of normal lymphocytes and tumor cells. Hydrolysis  The chemical alteration or decomposition of a compound into fragments by the addition of water. Hypercapnia  Excess amounts of carbon dioxide in the blood. Hyperemia  An excess or engorgement of blood in a part of the body. Hyperesthesia  An unusual or pathologic increase in sensitivity of a part, especially the skin, or of a particular sense. Hyperplasia  An abnormal multiplication or increase in the number of normal cells of a body part. Hypertonic  A solution having a greater concentra- tion of solute than another solution with which it is compared, hence exerting more osmotic pressure than that solution.

Hypertrophy  The enlargement or overgrowth of an organ that is due to an increase in the size of its cells rather than the number of its cells. Hypesthesia  An abnormal decrease of sensation in response to stimulation of the sensory nerves. (Also called hypoesthesia.) Hypocapnia  A deficiency of carbon dioxide in the blood. Hypotonic  A solution having a lesser concentration of solute than another solution with which it is com- pared, hence exerting less osmotic pressure than that solution. Hypoxia  An inadequate supply of oxygen to tissue that is below physiologic levels despite adequate perfusion of the tissue by blood. Iatrogenic  Induced inadvertently through the activity of a physician or by medical treatment or diagnostic procedures. Idiopathic  Arising spontaneously or from an unknown cause. Idiosyncrasy  A physical or behavioral characteristic or manner that is unique to an individual or group. (Adjective: idiosyncratic) Immunogenicity  The property that provides a substance with the capacity to produce an immune response. (Adjective: immunogenic) Incidence  The rate at which a certain event occurs (e.g., the number of new cases of a specific disease during a particular period of time in a population at risk). Inclusion  The act of enclosing or the condition of being enclosed; or anything that is enclosed. Indigenous  Native, or natural, to a particular country or region. Infarction  Necrosis or death of tissues due to local ischemia resulting from obstruction of blood flow. Inotropic  Influencing the force or energy of muscular contractions. In situ  In the natural or normal place; or something, such as cancer, that is confined to its place of origin and has not invaded neighboring tissues. Interferon  Any one of a group of small glycoproteins (cytokines) produced in response to viral infection and which inhibit viral replication. Interleukin  Any of several multifunctional cytokines produced by a variety of lymphoid and nonlym- phoid cells, including immune cells, that stimulate or otherwise affect the function of lymphopoietic and other cells and systems in the body. Interstitial  Relating to or situated between parts or in the interspaces of a tissue. Intramural  Situated or occurring within the wall of an organ. Intrinsic  Pertaining exclusively to a part or situated entirely within an organ or tissue. In vitro  A biologic reaction occurring in an artificial environment, such as a test tube. In vivo  A biologic reaction occurring within the living body. Involution  The act or instance of enfolding, entangling, or turning inward.