Porth's Essentials of Pathophysiology, 4e

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Glossary

Chemosis  Excessive edema of the mucous membrane of the eyeball and eyelid lining (conjunctiva). Chemotaxis  A response involving cell orientation or cell movement that is either toward (positive chemo- taxis) or away from (negative chemotaxis) a chemical stimulus. Chimeric  Relating to, derived from, or being an indi- vidual possessing one’s own immunologic character- istics and that of another individual; a phenomenon that can occur as the result of procedures such as a bone marrow graft. Chondrocyte  Any one of the mature polymorphic cells that form the cartilage of the body. Chromatid  One of the paired threadlike chromosome filaments, joined at the centromere, that make up a metaphase chromosome. Chromosome  Any one of the structures in the nucleus of a cell containing a linear thread of DNA, which functions in the transmission of genetic information. Chyme  The creamy, viscous, semifluid material pro- duced during digestion of a meal that is expelled by the stomach into the duodenum. Cilia  A minute, hairlike process projecting from a cell, composed of nine microtubules arrayed around a single pair. Cilia beat rhythmically to move the cell around in its environment, or they move mucus or fluids over the surface. Circadian  Being, having, pertaining to, or occurring in a period or cycle of approximately 24 hours. Circumduction  The active or passive circular move- ment of a limb or of the eye. Cisterna  An enclosed space, such as a cavity, that serves as a reservoir for lymph or other body fluids. Clathrin  The major structural coat protein of the coated vesicles involved in the intracellular transport between membranous organelles. Clone  One or a group of genetically identical cells or organisms derived from a single parent. Coagulation  The process of transforming a liquid into a semisolid mass, especially of blood clot formation. Coarctation  A condition of stricture or contraction of the walls of a vessel. Cofactor  A substance that must unite with another substance in order to function. Colic  Sharp, intermittent abdominal pain localized in a hollow or tubular organ, resulting from torsion, obstruction, or smooth muscle spasm. (Adjective: colicky) Collagen  The protein substance of the white, glistening, inelastic fibers of the skin, tendons, bone, cartilage, and all other connective tissue. Collateral  Secondary or accessory rather than direct or immediate; or a small branch, as of a blood vessel or nerve. Complement  Any one of the complex, enzymatic serum proteins that are involved in physiologic reactions, including antigen–antibody reaction and anaphylaxis. Confluent  Flowing or coming together; not discrete.

Congenital  Present at, and usually before, birth. Conjugate  To pair and fuse in conjugation; or a form of sexual reproduction seen in unicellular organisms in which genetic material is exchanged during the temporary fusion of two cells. Contiguous  In contact (or nearly so) in an unbroken sequence along a boundary or at a point. Contralateral  Affecting, pertaining to, or originating in the opposite side of a point or reference. Contusion  An injury of a part without a break in the skin, characterized by swelling, discoloration, and pain. Convolution  An elevation or tortuous winding, such as one of the irregular ridges on the surface of the brain, formed by a structure being folded in upon itself. Corpuscle  Any small mass, cell, or body, such as a red or white blood cell. Costal  Pertaining to a rib or ribs. Crepitus  A sound or sensation that resembles a crackling or grating noise. Cutaneous  Pertaining to the skin. Cyanosis  A bluish discoloration, especially of the skin and mucous membranes, caused by an excess of deoxygenated hemoglobin in the blood. Cytokine  Any of a class of polypeptide immunoregula- tory substances that are secreted by cells, usually of the immune system, that affect other cells. Cytology  The study of cells, including their origin, structure, function, and pathology. Cytosol  Cytoplasm exclusive of membranous compo- nents (e.g., mitochondria, endoplasmic reticulum) and nonmembranous insoluble components. Decibel  A unit for expressing the relative power sound intensity that is equal to one tenth of a bel. Defecation  The evacuation of feces from the digestive tract through the rectum. Deformation  The process of adapting in form or shape; also, the product of such alteration. Degeneration  The deterioration of a normal cell, tissue, or organ to a less functionally active form. (Adjective: degenerative) Deglutition  The act or process of swallowing. Degradation  The reduction of a chemical compound to a compound-less complex, usually by splitting off one or more groups. Dehydration  The condition that results from excessive loss of water from the body tissues. Delirium  An acute, reversible organic mental syndrome characterized by confusion, disorientation, restless- ness, incoherence, fear, and often illusions. Dendrite  One of the branching processes that extends and transmits impulses toward a cell body of a neuron. (Adjective: dendritic) De novo  Anew; often applied to the biochemical pathway where a complex biomolecule is synthesized in a new or different form from simple molecules. Depolarization  The reduction of a cell membrane potential to a less-negative value than that of the potential outside the cell.