Glossary of Terms

Dr. James Spahn

Abrasion The wearing or scraping away of a substance or structure, such as the skin, through an unusual or abnormal mechanical process. (2)

Abscess A collection of pus that is restricted to a specific area in tissues, organs, or confined spaces. (2)

Acid A substance that releases hydrogen ions when in a solution (compare with Base); a proton donor. (1)

Acid-base balance Situation in which the pH of the blood is maintained between 7.35 and 7.45. (1)

Acidosis State of abnormally high hydrogen ion concentration in the extracellular fluid. (1)

Adaptation Any change in structure or response to suit a new environment; (2) decline in the transmission of a sensory nerve when a receptor is stimulated continuously and without change in stimulus strength. (1)

Adaptation The adjustment of an organism to its environment, physical or psychological, through changes and responses to stress of any kind. (2)

Adipose tissue Areolar connective tissue modified to store nutrients; a connective tissue consisting chiefly of fat cells. (1)

Aerobic Oxygen-requiring. (1)

Aerobic Growing, living or occurring only in the presence of air or oxygen. (2)

Aerobic endurance The length of time a muscle can continue to contract using aerobic pathways. (1)

Akinesia An abnormal state in which there is an absence or poverty of movement. (2)

Alkalosis State of abnormally low hydrogen ion concentration in the extracellular fluid. (1)

Anabolism Energy-requiring building phase of metabolism in which simpler substances are combined to form more complex substances. (1)

Anabolism A constructive metabolic process characterized by the conversion of simple substances into larger, complex molecules. (2)

Anaerobic Not requiring oxygen. (1)

Anaerobic Growing, living, or occurring only in the absence of air or oxygen. (2)

Anaerobic glycolysis Energy-yielding conversion of glucose to lactic acid in various tissues, notably muscle, when sufficient oxygen is not available. (1)

Anaerobic threshold The point at which muscle metabolism converts to anaerobic glycolysis. (1)

Anaplasia A change in the structure of cells and in their orientation to each other that is characterized by a loss of cell differentiation, as in a cancerous cell growth. (2)

Anastomosis The connection or joining between two vessels; or an opening created by surgical, traumatic, or pathologic means. (2)

Anatomy Study of the structure of living organisms. (1)

Ankylose To fuse or obliterate through ankylosis, as in a joint. (2)

Ankylosis Stiffness or fixation of separate bones or hard parts, resulting from disease, injury, or surgical procedure. (2)

Glossary of Term Associated With Wound Care

Anterior Pertaining to a surface or part that is situated near or toward the front. (2)

Anorexia Lack or loss of appetite for food. (Adjective: anorexic) (2)

Anoxia Deficiency of oxygen. (1)

Anoxia An abnormal condition characterized by the total lack of oxygen. (2)

Aplasia The absence of an organ or tissue due to a developmental failure. (2)

Aponeurosis Fibrous or membranous sheet connecting a muscle and the part it moves. (1)

Areolar connective tissue A type of loose connective tissue. (1)

Arteries Blood vessels that conduct blood away from the heart and into the circulation. (1)

Arteriole A minute artery. (1)

Arteriosclerosis Any of a number of proliferative and degenerative changes in the arteries leading to their decreased elasticity. (1)

Articulation The place of connection or junction between two or more bones of the skeleton. (2)

Ascites An abnormal accumulation of serous fluid in the peritoneal cavity. (2)

Asepsis The condition of being free or freed from pathogenic microorganisms. (2)

Atherosclerosis Changes in the walls of large arteries consisting of lipid deposits on the artery walls; the early stage of arteriosclerosis. (1)

Atmospheric pressure Force that air experts on the surface of the body. (1)

Atrophy Reduction in size or wasting away of an organ or cell resulting from disease or lack of use. (1)

Ataxia An abnormal condition characterized by an inability to coordinate voluntary muscular movement. (2)

Atrophy A wasting or diminution of size or physiologic activity of a cell, tissue or organ. (2)

Autoimmune response Production of antibodies or effector T cells that attack a person’s own tissue. (1)

Autolysis Process of autodigestion (self digestion) of cells, especially dead or degenerate cells. (1)

Autoregulation The automatic adjustment of blood flow to a particular body area in response to its current requirements. (1)

Bacteremia The presence of bacteria in the blood. (2)

Baroreceptor A type of sensory nerve ending found in the walls of the atria of the heart, the vena cava, the aortic arch, and the carotid sinus that is stimulated by changes in pressure. (2)

Basal Pertaining to, situated at, or forming the base; or the fundamental of the basic. (2)

Basal metabolic rate (BMR) Rate at which energy is expended (heat produced) by the body per unit time under controlled (basal) conditions: 12 hours after a meal, at rest. (1)

Base A substance capable of binding with hydrogen ions; a proton acceptor. (1)

Basement membrane Extracellular material consisting of a basal lamina secreted by epithelial cells and a reticular lamina secreted by underlying connective tissue cells. (1)

Basophil A granulocytic white blood cell with irregularly shaped, segmented nucleus containing granules. (2)

Benign Not malignant; or of the character that does not threaten health or life. (2)

Blood pressure (BP) Force exerted by blood against a unit area of the blood vessel walls; differences in blood pressure between different areas of the circulation provide the driving force for blood circulation. (1)

Bone (osseous) tissue A connective tissue that forms the bony skeleton. (1)

Bone remodeling Process involving bone formation and destruction in response to hormonal and mechanical factors. (1)

Bone resorption The removal of osseous tissue; part of the continuous bone remodeling process. (1)

Boyle’s Law States that when the temperature is constant, the pressure of gas varies inversely with its volume. (1)

Bruit A sound or murmur heard while auscultating an organ or gland, especially an abnormal one. (2)

Buffer Chemical substance or system that minimizes changes in pH by releasing or binding hydrogen ions. (1)

Bulla A thin-walled blister of the skin or mucous membranes greater than 5mm in diameter containing serous or seropurulent fluid. (2)

Burn Tissue damage inflicted by intense heat, electricity, radiation or certain chemicals, all of which denature cell proteins and cause cell death in the affected areas. (1)

Bursa A fluid-filled sac or saclike cavity situated in places in the tissues at which friction would otherwise develop, such as between certain tendons and the bones beneath them. (2)

Cachexia A condition of general ill health and malnutrition, marked by weakness and emaciation. (2)

Calcaneal tendon Tendon that attaches the calf muscles to the heelbone (calcaneus); also called the Achilles tendon. (1)

Callus (1)Localized thickening of the skin epidermis resulting from physical trauma; (2)repair tissue (fibrous or bony) formed at a fracture site. (1)

Calorie (cal) Amount of energy needed to raise the temperature of 1 gram of water 1° Celsius. Energy exchanges associated with biochemical reactions are usually reported in kilocalories (1 kal = 1000 cal) or large calories (Cal). (1)

Cancer A malignant, invasive cellular neoplasm that has the capability of spreading throughout the body or body parts. (1)

Capillaries The smallest of the blood vessels and the sites of exchange between the blood and tissue cells. (1)

Carbonic acid-bicarbonate system Chemical buffer system that helps maintain pH homeostasis of the blood. (1)

Carbohydrate Organic compound composed of carbon, hydrogen, and oxygen; includes starches, sugars and cellulose. (1)

Carcinogen Any substance or agent that causes the development or increases the incidence of cancer. (2)

Cardiac output (CO) Amount of blood pumped out of a ventricle in one minute. (1)

Cardiac reserve The difference between resting and minimal cardiac output. (1)

Cardiovascular system Organ system which distributes the blood to deliver nutrients and remove wastes. (1)

Cartilage White, semiopaque connective tissue. (1)

Cartilage bone (endochondral bone) Bone formed by the calcification of hyaline cartilage structures. (1)

Caseation A form of tissue necrosis in which the tissue is changed into a dry, amorphous mass resembling crumbly cheese. (2)

Catabolism Process in which living cells break down substances into simpler substances. (1)

Catabolism A metabolic process through which living organisms break down complex substances to simple compounds, liberating energy for use in work, energy storage, or heat production. (2)

Caudal Literally, toward the tail; in humans, the inferior portion of the anatomy. (1)

Cell-mediated immune response Immunity conferred by activated T cells, which directly lyse infected or cancerous body cells or cells of foreign grafts and release chemicals that regulate the immune response. (1)

Cellular respiration Metabolic processes in which ATP is produced. (1)

Cellulitis An acute, diffuse, spreading, edematous inflammation of the deep subcutaneous tissues and sometimes muscle, characterized most commonly by an area of heat, redness, pain, and swelling, and occasionally by fever, malaise, chills, and headache. (2)

Chemoreceptor A sensory nerve cell activated by chemical stimuli, as a chemoreceptor in the carotid that is sensitive to changes in the oxygen content in the bloodstream and reflexly increases or decreases respiration and blood pressure. (2)

Chemotaxis A response involving cell orientation or cell movement that is either toward (positive chemotaxis) or away from (negative chemotaxis) a chemical stimulus. (2)

Coagulation Process by which blood is transformed from a liquid to a gel; blood clotting. (1)

Coagulation The process of transforming a liquid into a semisolid mass, especially of blood clot formation. (2)

Coarctation A condition of stricture or contraction of the walls of a vessel. (2)

Collagen The protein substance of white, glistening, inelastic fibers of the skin, tendons, bone, cartilage, and all other connective tissue. (2)

Collateral Secondary or accessory rather than direct or immediate; or a small branch, as of a blood vessel or nerve. (2)

Colloid A mixture in which the solute particles do not settle out readily and do not pass through natural membranes. (1)

Colloidal osmotic pressure Pressure created in a fluid by large nondiffusible molecules, such as plasma proteins that are prevented from moving through a (capillary) membrane. Such substances tend to draw water to them. (1)

Complement A group of bloodborne proteins, which, when activated, enhance the inflammatory and immune responses and may lead to cell lysis. (1)

Concentration gradient The difference in the concentration of a particular substance between two areas. (1)

Connective tissue A primary tissue; form and function vary extensively. Functions include support, storage and protection. (1)

Contusion An injury of a part without the break in the skin, characterized by swelling, discoloration, and pain. (2)

Corpuscle Any small mass, cell, or body, such as a red or white blood cell. (2)

Creatine kinase Enzyme that catalyzes the transfer of phosphate from phosphocreatine to ADP, forming creatine and ATP; important in muscle contraction. (1)

Crepitus Flatulence or noisy discharge of fetid gas from the bowels; or a sound that resembles a crackling noise. (2)

Cutaneous Pertaining to the skin. (1)

Cutaneous Pertaining to the skin. (2)

Cutaneous sensory receptors Receptors located throughout the skin that respond to stimuli arising outside the body; part of the nervous system. (1)

Cyanosis A bluish discoloration, especially of the skin and mucous membranes, caused by an excess of deoxygenated hemoglobin in the blood. (2)

Cytology The study of cells, including their origin, structure, function, and pathology. (2)

Deformation The process of adapting in form or shape; also the product of such alteration. (2)

Degeneration The deterioration of a normal cell, tissue, or organ to a less functionally active form. (Adjective: degenerative) (2)

Dehydration Condition of excessive water loss. (1)

Dehydration The condition that results from excessive loss of water from the body tissues. (2)

Delirium An acute, reversible organic mental syndrome characterized by confusion, disorientation, restlessness, incoherence, fear, anxiety, excitement, often illusions and hallucinations, and at times delusions. (2)

Dermis Layer of skin deep to the epidermis; composed of dense irregular tissue. (1)

Desquamation A normal process in which the cornified layer of the epidermis is shed in fine scales or sheets. (2)

Diabetes mellitus Disease caused by deficient insulin release, leading to inability of the body cells to use carbohydrates. (1)

Diapedesis Passage of blood cells through intact vessel walls into tissue. (1)

Diastole Period of the cardiac cycle when either the ventricles or the atria are relaxing. (1)

Diastolic pressure Arterial blood pressure reached during or as a result of diastole; lowest level of any given ventricular cycle. (1)

Digestion Chemical or mechanical process of breaking down foodstuffs to substances that can be absorbed. (1)

Digestive system System that processes food into absorbable units and eliminates indigestible wastes. (1)

Dyskinesia Disorders of muscle tone, posture, or involuntary movements. (1)

Ectoderm Embryonic germ layer; forms the epidermis of the skin and its derivatives, and nervous tissues. (1)

Edema Abnormal accumulation of fluid in body parts or tissues; causes swelling. (1)

Elastic cartilage Cartilage with abundant elastic fibers; more flexible than hyaline cartilage. (1)

Electrolyte Chemical substances, such as salts, acids and bases, that ionize and dissociate in water and are capable of conducting an electrical current. (1)

Electrolyte balance Refers to the balance between input and output of salts (sodium, potassium, calcium, magnesium) in the body. (1)

Element One of a limited number of unique varieties of matter that composes substances of all kinds; e.g., carbon, hydrogen, oxygen. (1)

Embolism Obstruction of a blood vessel by an embolus (blood clot, fatty mass, bubble of air, or other debris) floating in the blood. (1)

Embryo Developmental stage extending from gastrulation to the end of the eight week. (1)

Endoderm Embryonic germ layer; forms the lining of the digestive tube and its associated structures. (1)

Endomysium Thin connective tissue surrounding each muscle cell. (1)

Endosteum Connective tissue membrane covering internal bone surfaces. (1)

Endothelium Single layer of simple squamous cells that line the walls of the heart, blood vessels, and lymphatic vessels. (1)

Energy The capacity to do work; may be stored (potential energy) of in action (kinetic energy) (1)

Energy intake Energy liberated during food oxidation. (1)

Energy output Sum of energy lost as heat, as work, and as fat or glycogen storage. (1)

Enzyme A protein that acts as a biological catalyst to speed up a chemical reaction. (1)

Epidermis Superficial layer of skin; composed of keratinized stratified squamous epithelium. (1)

Epithelium (epithelial tissue) Pertaining to a primary tissue that covers the body surface, lines its internal cavities, and forms glands. (1)

Erythrocytes Red blood cells. (1)

Erythropoiesis Process of erythrocyte formation. (1)

Extension Movement that increases the angle of a joint, e.g., straightening a flexed knee. (1)

Extracellular fluid Internal fluid located outside the cell; includes plasma and interstitial fluid. (1)

Extracellular materials Nonliving material that separates the living cells in connective tissue consisting of ground substance and fibers. (1)

Extracellular matrix Nonliving material that separates the living cells in connective tissue consisting of ground substance and fibers. (1)

Exudate Material including fluid, pus, or cells that has escaped from blood vessels and has been deposited in tissues. (1)

Fascia Layers of fibrous tissue covering and separating muscle. (1)

Fascicle Bundle of nerve or muscle fibers bound together by connective tissues. (1)

Fetus Developmental stage extending from the ninth week of development to birth. (1)

Fibroblast Young, actively mitotic cell that forms the fibers of connective tissue. (1)

Fibrocyte Mature fibroblast; maintains the matrix of fibrous types of connective tissue. (1)

First-degree burn A burn which only the epidermis is damaged. (1)

Free radicals Highly reactive chemicals with unpaired electrons that can scramble the structure of proteins, lipids, and nucleic acids. (1)

Germ layers Three cellular layers (ectoderm, mesoderm, and endoderm) that represent the initial specialization of cells in the embryonic body and from which all body tissues arise. (1)

Hair follicle Structure with outer and inner root sheaths extending from the epidermal surface into the dermis and from which new hair develops. (1)

Hematocrit The percentage of erythrocytes to total blood volume. (1)

Hematoma Mass of clotted blood that forms at an injured site. (1)

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. (2)

Hematopoiesis The normal formation and development of blood cells. (2)

Hemoglobin Oxygen-transporting component of erythrocytes. (1)

Hemorrhage Loss of blood from the vessels by flow through ruptured walls; bleeding. (1)

Hemostasis Stoppage of bleeding. (1)

Homeostasis A state of body equilibrium or stable internal environment of the body. (1)

Hyaline cartilage The most abundant cartilage type in the body; provides firm support with some pliability. (1)

Hydrostatic pressure Pressure of fluid in a system. (1)

Hydroxyl ion (OH¯) An ion liberated when a hydroxide (a common inorganic base) is dissolved in water. (1)

Hyperemia An increase in blood flow into a tissue or organ; congested with blood. (1)

Hyperemia An excess or engorgement of blood in a part of the body. (2)

Hyperesthesia An unusual or pathologic increase in sensitivity of a part, especially the skin, or of a particular sense. (2)

Hyperplasia An abnormal multiplication or increase in the number of normal cells of a body part. (2)

Hypertonic A solution having a greater concentration of solute than another solution with which it is compared, hence exerting more osmotic pressure than that solution. (2)

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. (2)

Hypesthesia An abnormal decrease of sensation in response to stimulation of the sensory nerves. (Also called hypoesthesia) (2)

Hypodermis (superficial fascia) Subcutaneous tissue just deep to the skin; consists of adipose plus some areolar connective tissue. (1)

Hypoproteinemia A condition of unusually low levels of plasma proteins causing a reduction in colloid osmotic pressure; results in tissue edema. (1)

Hypotonic A solution having a lesser concentration of solute than another solution with which it is compared, hence exerting less osmotic pressure than that solution. (2)

Hypoxia Condition in which inadequate oxygen is available to tissues. (1)

Hypoxia An inadequate supply of oxygen to tissue that is below physiologic levels despite adequate perfusion of the tissue by blood. (2)

Iatrogenic Induced inadvertently through the activity of a physician or by medical treatment or diagnostic procedures. (2)

Idiopathic Arising spontaneously or from an unknown cause. (2)

Idiosyncrasy A physical or behavioral characteristic or manner that is unique to an individual or to a group. (Adjective: idiosyncratic) (2)

Immune system A functional system whose components attack foreign substances or prevent their entry into the body. (1)

Immunodeficiency disease Disease resulting form the deficient production or function of immune cells or certain molecules (complement, antibodies, etc) required for normal immunity. (1)

In vitro In a test tube, glass, or artificial environment. (1)

In vivo In the living body. (1)

Incontinence Inability to control micturition voluntarily. (1)

Infarct Region of dead, deteriorating tissue resulting from a lack of blood supply. (1)

Infarction The development and formation of an infarct; or an infarct. (2)

Inflammation A nonspecific defensive response of the body to tissue injury; includes dilation of blood vessels and an increase in vessel permeability; indicated by redness, heat, swelling and pain. (1)

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. (2)

Integumentary system Skin and its derivatives; provides the external protective covering of the body. (1)

Interstitial Relating to or situated between parts or in the interspaces of a tissue. (2)

Interstitial fluid Fluid between the cells. (1)

Intracellular fluid Fluid within a cell. (1)

Intramural Situated or occurring within the wall of an organ. (2)

In vitro A biologic reaction occurring in an artificial environment, such as a test tube. (2)

In vivo A biologic reaction occurring within the living body. (2)

Ischemia Local decrease in blood supply. (1)

Ischemia Decreased blood supply to a body organ or part, usually due to functional constriction or actual obstruction of a blood vessel. (2)

Keratin Water-soluble protein found in the epidermis, hair, and nails that makes those structures hard and water-repellant; precursor is keratohyalin. (1)

Keratin A fibrous, sulfur-containing protein that is the primary component of the epidermis, hair and horny tissues. (2)

Keratinization The development or conversion into keratin or keratinous tissue. (2)

Keratosis Any skin condition in which there is overgrowth and thickening of the cornified epithelium. (2)

Ketones Fatty acid metabolites; strong organic acids. (1)

Ketosis Abnormal condition during which an excess of ketone bodies is produced. (1)

Kinesthesia The sense of movement, weight, tension, and position of body parts mediated by input from joint and muscle receptors and hair cells. (Adjective: kinesthetic) (2)

Krebs cycle Aerobic metabolic pathway occurring within mitochondria, in which food metabolites are oxidized and CO_ is liberated, and coenzymes are reduced. (1)

Kyphosis A small pit or cavity within a structure, especially bony tissue; or a defect or gap, as in the field of vision. (2)

Lactic acid Product of anaerobic metabolism, especially in muscle. (1)

Leukocytes White blood cells; formed elements involved in body protection that take part in inflammatory and immune responses. (1)

Leukocytosis An increase in the number of leukocytes (white blood cells); usually the result of a microbiological attack on the body. (1)

Leukopenia Abnormally low white blood cell count. (1)

Leukopoiesis The production of white blood cells. (1)

Ligament One of the many predominantly white, shiny, flexible bands of fibrous tissue that binds joints together and connects bones and cartilages. (2)

Lipid Organic compound formed of carbon, hydrogen, and oxygen; examples are fat and cholesterol. (1)

Lipid Any of the group of fats and fatlike substances characterized by being insoluble in water and soluble in nonpolar organic solvents, such as chloroform and ether. (2)

Lipoprotein Any one of the conjugated proteins that is a complex of protein and lipid. (2)

Lordosis The anterior concavity in the curvature of the lumbar and cervical spine as observed from the side. (2)

Lumen A cavity or the channel within a tube or tubular organ of the body. (2)

Lymph Protein-containing fluid transported by a lymphatic vessels. (1)

Lymph node Small lymphatic organ that filters lymph; contains macrophages and lymphocytes. (1)

Lymphatic System System consisting of lymphatic vessels, lymph nodes, and other lymphoid organs and tissues; drains excess tissue fluid from the extracellular space and provides a site for immune surveillance. (1)

Lymphatics General term used to designate the lymphatic vessels that collect and transport lymph. (1)

Lymphocyte Agranular white blood cell that arises from bone marrow and becomes functionally mature in the lymphoid organs in the body. (1)

Lymphokines Proteins involved in cell-mediated immune responses that enhance immune and inflammatory responses. (1)

Lysis Destruction or dissolution of a cell or molecule through the action of a specific agent. (2)

Lysozyme Enzyme in sweat, saliva, and tears that is capable of destroying certain kinds of bacteria. (1)

Macerate To soften something solid by wetting or soaking. (2)

Macrophage Protective cell type common in connective tissues, lymphatic tissue, and certain body organs that phagocytizes tissue cells, bacteria, and other foreign debris; important as an antigen-presenter to T cells and B cells in the immune response. (1)

Macula A small, flat blemish, thickening, or discoloration that is flush with the skin surface. (Adjective: macular) (2)

Malaise A vague feeling of bodily fatigue and discomfort. (2)

Malignant Life threatening; pertains to neoplasms that spread and lead to death, such as cancer. (1)

Manometer A device for measuring the tension or pressure of a liquid or gas. (2)

Manometry The measurement of pressure using a manometer. (2)

Marasmus A condition of extreme protein-calorie malnutrition that is characterized by growth retardation and progressive wasting of subcutaneous tissue and muscle and occurs chiefly during the first year of life. (2)

Mast cells Immune cells that function to detect foreign substances in the tissue spaces and initiate local inflammatory responses against them; typically found clustered deep to an epithelium or along blood vessels. (1)

Matrix The intracellular substance of a tissue or the basic substance from which a specific organ or kind of tissue develops. (2)

Melanin Dark pigment formed by cells called melanocytes; imparts color to skin and hair. (1)

Mesenchyme Common embryonic tissue from which all connective tissues arise. (1)

Mesoderm Primary germ layer that forms the skeleton and muscles of the body. (1)

Mesoderm The middle layer of the three primary germ layers of the developing embryo, lying between the ectoderm and the endoderm. (2)

Metabolic rate Energy expended by the body per unit time. (1)

Metabolism Sum total of the chemical reactions occurring in the body cells. (1)

Metabolism The sum of all the physical and chemical processes by which living organisms are produced and maintained, and also the transformation by which energy is provided for vital processes and activities. (2)

Metastasis The transfer of diseases from one organ or part to another not directly connected with it. (Adjective: metastatic) (2)

Micturition Urination, or voiding; emptying the bladder. (1)

Molecule The smallest mass of matter that exhibits the properties of an element or compound. (2)

Monocyte Large single-nucleus white blood cell; agranular leukocyte. (1)

Monokines Chemical mediators that enhance the immune response; secreted by macrophages. (1)

Mucous membranes Membranes that form the linings of body cavities open to the exterior (digestive, respiratory, urinary, and reproductive tracts). (1)

Muscular system The organ system consisting of the skeletal muscles of the body and their connective tissue attachments. (1)

Mutation An unusual change in form, quality, or some other characteristic; or a permanent transmissible change in genetic material occurring spontaneously or by induction. (2)

Myoclonus A spasm of a portion of a muscle, an entire muscle, or a group of muscles. (2)

Myopathy Any disease or abnormal condition of the skeletal muscle, usually characterized by muscle weakness, wasting, and histologic changes within muscle tissue. (2)

Necrosis Death or disintegration of a cell or tissues caused by disease or injury. (1)

Necrosis Localized tissue death that occurs in groups of cells or part of a structure or an organ in response to disease or injury. (2)

Negative feedback mechanisms The most common homeostatic control mechanism. The net effect is that the output of the system shuts off the original stimulus or reduces its intensity. (1)

Neoplasm An abnormal mass of proliferating cells; benign neoplasms remain localized; malignant neoplasms are cancers, which can spread to other organs. (1)

Neutropenia An abnormal decrease in the number of neutrophilic leukocytes in the blood. (2)

Neutrophil Most abundant type of white blood cell. (1)

Nidus The point where a morbid process originates, develops, or is located. (2)

Nociceptor Receptor sensitive to potentially damaging stimuli that result in pain. (1)

Nociceptor A receptor, usually found in either the skin or the walls of the viscera, that responds to pain caused by injury to body tissues. (2)

Nosocomial Pertaining to or originating in a hospital, such as a nosocomial infection; an infection acquired during hospitalization. (2)

Nutrients Chemical substances taken in via the diet that are used for energy and cell building. (1)

Occlusion Closure or obstruction. (1)

Orthopnea An abnormal condition in which a person must be in an upright position in order to breathe deeply or comfortably. (2)

Osmolality The concentration of osmotically active particles in solution expressed in osmols or milliosmols per kilogram of solvent. (2)

Osmolarity The concentration of osmotically active particles in solution expressed in osmols or milliosmols per liter of solution. (2)

Osmosis The movement or passage of a pure solvent such as water, through a semipermeable membrane from a solution that has a lower solute concentration to one that has a higher solute concentration. (2)

Osteophyte A bony project or outgrowth. (2)

Oxyhemoglobin Oxygen-bound form of hemoglobin. (1)

Palpable Perceptible by touch. (2)

Papule A small circumscribed, solid elevation of the skin less than one centimeter in diameter. (Adjective: papular) (2)

Paralysis An abnormal condition characterized by the impairment or loss of motor function or the loss of sensation, or both, due to a lesion of the neural or muscular mechanism. (2)

Parenchyma The basic tissue or elements of an organ as distinguished from supporting or connective tissue or elements. (Adjective: parenchymal) (2)

Paresis Slight or partial paralysis. (2)

Paresthesia Any abnormal touch sensation, which can be experienced as numbness, tingling, or a “pins and needles” feeling, often in the absence of external stimuli. (2)

Passive immunity Short-lived immunity resulting from the introduction of “borrowed antibodies” obtained from an immune animal or human donor; immunological memory is not established. (1)

Pathogen Disease-causing microorganism. (1)

Pathogen Any microorganism capable of producing disease. (2)

Perfusion The process or act of pouring over or through, especially the passage of fluid through a specific organ or an area of the body. (2)

Perimysium Connective tissue enveloping bundles of muscle fibers. (1)

Periosteum Double-layered connective tissue that covers and nourishes the bone. (1)

Peripheral Pertaining to the outside, surface, or surrounding area of an organ or other structure; or located away from the center or central structure. (2)

Peripheral congestion Condition caused by failure of the right side of the heart; results in edema in the extremities. (1)

Permeable A condition of being pervious, or permitting passage, so that fluids and certain other substances can pass through, as a permeable membrane. (2)

Petechia A tiny, perfectly round purplish red spot that appears on the skin as a result of minute intradermal or submucous hemorrhage. (Plural: petechiae) (2)

Petechiae Small, purplish skin blotches caused by widespread hemorrhage due to thrombocytopenia. (1)

Phagocytosis Engulfing of foreign solids by (phagocytic) cells. (1)

Phagocytosis The process by which certain cells engulf and consume foreign material and cell debris. (2)

Phalanx Any one of the bones composing the fingers of each hand and the toes of each foot. (2)

Physiology Study of the function of living organisms. (1)

Plasma The nonliving fluid component of blood within which formed elements and various solutes are suspended and circulated. (1)

Plasma cells Members of a B cell clone; specialized to produce and release antibodies. (1)

Platelet Cell fragment found in blood; involved in clotting. (1)

Positive feedback mechanisms Feedback that tends to cause the level of a variable to change in the same direction as an initial change. (1)

Prolapse The falling down, sinking, or sliding of an organ from its normal position or location in the body. (2)

Prone The position in which the ventral, or front, surface of the body faces downward. (2)

Proprioception The reception of stimuli originating from within the body regarding body position and muscular activity. (2)

Proprioceptor Any of the sensory nerve endings, found in muscles, tendons, joints, and the vestibular apparatus, that respond to stimuli originating from within the body regarding movement and body position. (2)

Protein Complex substance containing carbon, oxygen, hydrogen, and nitrogen; composes 10% to 30% of cell mass. (1)

Prothesis An artificial replacement for a missing body part; or a device designed and applied to improve function, such as a hearing aid. (2)

Proximal Closer to a point of reference, usually the trunk of the body, than other parts of the body. (2)

Pruritus The symptom of itching, an uncomfortable sensation leading to the urge to rub or scratch the skin to obtain relief. (Adjective: pruritic) (2)

Pulse Rhythmic expansion and recoil of arteries resulting from heart contraction; can be felt from outside the body. (1)

Purpura A small hemorrhage, up to about 1 cm in diameter , in the skin, mucous membrane, or serosal surface; or any of several bleeding disorders characterized by the presence of purpuric lesions. (2)

Purulent Producing or containing pus. (2)

Pus Fluid product of inflammation composed of white blood cells, the debris of dead cells, and a thin fluid. (1)

Quiescent Causing no disturbance, activity, or symptoms. (2)

Resistance exercise High-intensity exercise in which the muscles are pitted against high resistance or immovable forces and, as a result, muscle cells increase in size. (1)

Resorption The loss of substance or bone by physiologic or pathologic means, for example, the loss of dentin and cementum of a tooth. (2)

Respiratory system Organ system that carries out gas exchange; includes the nose, pharynx, larynx, trachea, bronchi, lungs. (1)

Sclerosis A condition characterized by induration or hardening of tissue resulting from any several causes, including inflammation, diseases of the interstitial substance, and increased formation of connective tissue. (2)

Sebaceous glands (oil glands) Epidermal glands that produce an oily secretion called sebum. (1)

Sebum Oily secretion of the sebaceous glands. (1)

Second-degree burn A burn in which the epidermis and the upper region of the dermis are damaged. (1)

Semipermeable partially but not wholly permeable, especially a membrane that permits the passage of some (usually small) molecules but not of other (usually larger) particles. (2)

Senescence The process or condition of aging or growing old. (2)

Sepsis The presence in the blood or other tissues of pathogenic microorganisms or their toxins; or the condition resulting from the spread of microorganisms or their products. (Adjective: septic) (2)

Skeletal cartilage Comprises most of the skeleton in early fetal life; articular cartilage, nasal cartilage in the adult skeleton. (1)

Skeletal muscle Muscle composed of cylindrical multinucleate cells with obvious striations; the muscle(s) attached to the body’s skeleton; voluntary muscle. (1)

Skeletal system System of protection and support composed primarily of bone and cartilage. (1)

Sodium-potassium (Na+ -K+) pump A primary active transport system that simultaneously drives Na_ out of the cell against a steep gradient and pumps K_ back in. (1)

Sol-gel transformation Reversible change of a colloid from a fluid (sol) to a more solid (gel) state. (1)

Spastic Pertaining to or characterized by spasms or other uncontrolled contractions of the skeletal muscles. (2)

Sphincter A ringlike band of muscle fibers that constricts a passage or closes a natural orifice of the body. (2)

Stenosis An abnormal condition characterized by the narrowing or stricture of a duct or canal. (2)

Stria A streak or linear scarlike lesion that often results from rapidly developing tension in the skin; or a narrow bandlike structure, especially the longitudinal collections of nerve fibers in the brain. (2)

Stricture An abnormal temporary or permanent narrowing of the lumen of a duct, canal, or other passage, as the esophagus, because of inflammation, external pressure or scarring. (2)

Stroma The supporting tissue or the matrix of an organ as distinguished from its functional element, or parenchyma. (2)

Stupor A lowered level of consciousness characterized by lethargy and unresponsiveness in which a person seems unaware of his or her surroundings. (2)

Subcutaneous Beneath the skin. (1)

Subcutaneous Beneath the skin. (2)

Supine Lying horizontally on the back, or with the face upward. (2)

Suppuration The formation of pus, or purulent matter. (2)

Syncope A brief lapse of consciousness due to generalized cerebral ischemia. (2)

Syndrome A complex of signs and symptoms that occur together to present a clinical picture of a disease or inherited abnormality. (2)

Systemic Pertaining to the whole body. (1)

Systemic circuit System of blood vessels that serves gas exchange in the body tissues. (1)

Systole Period when either the ventricles of the atria are contracting. (1)

Systolic pressure Pressure exerted by blood on the blood vessel walls during ventricular contractions. (1)

T cells Lymphocytes that mediate cellular immunity; include helper, killer, suppressor and memory cells. Also called T lymphocytes. (1)

Tamponade Stoppage of the flow of blood to an organ or a part of the body by pathologic compression, such as the compression of the heart by an accumulation of pericardial fluid. (2)

Tendon Cord of dense fibrous tissue attaching muscle to bone. (1)

Third degree burn A burn that involves the entire thickness of the skin; also called a full-thickness burn. Usually requires skin grafting. (1)

Thrombus A clot that develops and persists in an unbroken blood vessel. (1)

Tissue A group of similar cells and their intercellular substance specialized to perform a specific function; primary tissue types of the body are epithelial, connective, muscle, and nervous tissue. (1)

Tissue perfusion Blood flow through body tissues or organs. (1)

Torsion The act or process of twisting in either a positive (clockwise) or negative (counterclockwise) direction. (2)

Transudate A fluid substance passed through a membrane or extruded from the blood. (2)

Tremor Involuntary quivering or trembling movements caused by the alternating contraction and relaxation of opposing groups of skeletal muscles. (2)

Ulcer Lesion or erosion of the mucous membrane, such as gastric ulcer of the stomach. (1)

Ulcer A circumscribed excavation of the surface of an organ or tissue, which results from necrosis that accompanies some inflammatory, infectious, or malignant processes. (adjective: ulcerative) (2)

Urinary System System primarily responsible for water, electrolyte, and acid-base balance and removal of nitrogenous wastes. (1)

Uticaria A pruritic skin eruption of the upper dermis, usually transient, characterized by wheals of various shapes and sizes. (2)

Vascular Pertaining to blood vessels or richly supplied with blood vessels. (1)

Vascular spasm Immediate response to blood vessel injury; results in constriction. (1)

Vasoconstriction Narrowing of blood vessels. (1)

Vasodilation Relaxation of the smooth muscles of the blood vessels producing dilation. (1)

Vasomotion Intermittent contraction or relaxation of the precapillary sphincter beds resulting in a staggered blood flow when tissue needs are not extreme. (1)

Veins Blood vessels that return blood toward the heart from the circulation. (1)

Venule A small vein. (1)

Vesicle A small bladder or sac, as a small, thin-walled, raised skin lesion, containing liquid. (2)

Visceral Pertaining to the viscera, or internal organs of the body. (2)

Viscosity State of being sticky or thick. (1)

Viscosity Pertaining to the physical property of fluids, caused by the adhesion of adjacent molecules, that determines the internal resistance to shear forces. (2)

Vital signs Includes pulse, blood pressure, respiratory rate, and body temperature measurements. (1)

(1) Marieb, Elaine, Human Anatomy & Physiology. San Francisco, California: Benjamin Cummings, 2001.

(2) Porth, Carol Mattson, Pathophysiology – Concepts of Altered Health States.

Philadelphia, Pennsylvania: Lippincott-Raven Publishers, 1998.