^o C : Celsius/Centigrade.

C&S : Culture and sensitivity.

Cachexia : Severe debilitated state (heavy worm infestation, visceral leishmaniasis).

CAE : Cellulose acetate electrophoresis.

Calabar swellings : Transient swellings of subcutaneous tissues; associated with Loa loa infections.

Calcerous corpuscles : Rounded masses composed of concentric layers of calcium carbonate that are found in the tissue of tapeworms, characteristic of tapeworm tissue; certain fixatives must be avoided in order to preserve presence of corpuscles for identification purposes (tapeworms).

Calcifications : Portions of tissue (host, parasite) that become hardened by the deposition of calcium salts; may be visible on radiographic studies (toxoplasmosis, cysticercosis, trichinosis, schistosomiasis).

Calibrated loop : Bacteriological loop that is carefully calibrated to deliver a specified volume of fluid providing that directions are followed carefully and the loop has not been damaged; used as a simple means of quantitating the number of organisms present, especially for urine culture.

Calvin cycle : The biochemical route of carbon dioxide fixation in many autotrophic organisms.

Camp : Lytic factor named after Christie, Atkins, and Munch-Peterseon.

Cancer : A malignant, invasive cellular tumor that has the capability of spreading throughout the body or body parts.

Candle jar :A Jar with a lid providing a gas-tight seal in which a small white candle is placed and lit after the culture plates have been placed inside. Candle will burn only until the oxygen concentration has been lowered to the point where it will no longer support the flame. Atmosphere of such a jar has a lower oxygen content than room air and a carbon dioxide content of about 3%.

Cannula : An artificial tube for insertion into a tube or cavity of the body.

CAP : Chocolate agar plate.

CAPD : Chronic ambulatory peritoneal dialysis.

Capneic incubation :Incubation under increased CO2 tension, as in a candle extinction jar (approximate 3% CO2).

Capnophilic :Term used to describe microorganisms that prefer an incubation atmosphere with increased carbon dioxide concentration.

Capsid : Protein layer or coat surrounding viral nucleic acid core.

Capsomere : Protein subunits that serve as components of the viral capsid.

Capsule : A colorless, transparent, mucopolysaccharide sheath on the wall of a cell.

Carbohydrate : Any chemical compound which consists of only carbon (C), oxygen (O), and hydrogen (H) elements, for example, sugars, starches, and cellulose are carbohydrates. Also, the ratio of hydrogen to oxygen atoms in carbohydrates is usually 2:1.

Carboxyl group : -COOH

Carboxysomes : Polyhedral cellular inclusions of crystaline ribulose bisphosphate carboxylase (RubisCO), the key enzyme of the Calvin cycle.

Carcinogen : A substance which causes the initiation of tumor formation. Frequently mutagen.

Carditis : Inflammation of the heart tissues (Chagas' disease).

Carrier : A person or animal that harbors a specific infectious agent without discernible clinical disease and serves as a potential source of infection.

Case-fatatlity rate : Usually expressed as the percentage of persons diagnosed as having a specified disease who die as a result of that illness within a given period.

CAT : Computerized (axial) tomography scan.

Catabolism : The biochemical processes involved in the breakdown of organic compounds, usually leading to the production of energy.

Catabolite repression : Repression of a variety of unrelated enzymes when cells are grown in a medium containing glucose.

Catalase : An enzyme that destroys hydrogen peroxide by catalyzing the reaction 2H202 - 2H20+02.

Catalysis : Increase in rate of a chemical reaction.

Catalyst : A substance that promotes a chemical reaction by lowering the activation energy without itself being changed in the end. Enzyme is a type of catalyst.

Cathartic : A substance causing evacuation of bowels by increasing bulk, stimulating peristalsis.

Catheter :Flexible tubular (rubber or plastic) instrument used for withdrawing fluids from (or introducing fluids into) a body cavity or vessel (e.g., urinary bladder catheter).

Catheterization : The placement of a catheter, usually through the urethra, into the bladder in order to drain urine from the bladder.

Cation : A positive ion.

CBC : Complete blood (cell) count.

cc : Cubic centimeter.

CD : Clusters of differentiation.

CDC : Centers for Disease Control.

cDNA : Complementary DNA.

CD4 cells : T helper cells which are targets for HIV infection.

Cecum : A blindly ending appendage of the intestine.

Cell : The fundamental unit of living matter.

Cell line : A cell culture that has been passed (subcultured) in vitro.

Cell line, continuous : Line of tissue cells that is maintained by serial culture of an established cell line.

Cell line, primary : Line of tissue cells established by cutting up fresh tissue, often kidney, into tiny pieces, trypsinizing, and putting in a flask with appropriate medium.

Cell-mediated immunity : An immune response generated by the activities of non-antibody-producing cells such as T cells. Compare with humoral immunity.

Cell membrane : See cytoplasmic membrane.

Cell wall : The layer or structure that lies outside the cytoplasmic membrane; it supports and protects the membrane and gives the cell shape.

Cellular microbiology : A new discipline emerging at the interface between cell biology and microbiology. One major focus of this new field is on the interference of pathogenic bacteria with many eukaryotic cell functions, such as maturation of intracellular compartments, internal cellular communication, or even cell division and differentiation. The study of cellular microbiology in this respect, is providing a sophisticated tool kit for mammalian cell biologists. (Ref

Cellulitis : Inflammation of subcutaneous tissue.

Cellulose : A glucose polysaccharide (with beta-1,4-linkage) that is the main component of plant cell walls.

Cercaria : Free-living, tailed larval stage of trematodes; may infect humans by direct penetration (schistosomes); may attach to vegetation and encyst to metacercarial stage (Fasciola and Fasciolopsis spp.), or may penetrate tissues of vertebrates or invertebrates and encyst to metacercarial stage (Clonorchis spp.).

Cerebellar : Pertaining to the cerebellum (the portion of the brain concerning the coordination of complex movements and balance).

Cerebiform :With brainlike folds.

Cerebrospinal fluids : Fluid surrounding the brain and spinal cord.

Cervical : Pertaining either to the neck or to the cervix of the uterus.

Cervicitis : Inflammation of the mucous membranes or deeper structures of the cervix.

Cessation necrosis : Tissue death with loss of cell outlines and a cheeselike, amorphous appearance.

Cestode : Tapeworm.

CF :Complement fixation.

CFU :Colony-forming unit (i.e., colony count).

C2 H6O : Ethyl alcohol.

CH2 O : Formaldehyde.

CH4 O : Methyl alcohol.

Chagas' disease : Infection caused by Trypanosoma cruzi (South American trypanosomiasis).

Chagoma :Small granuloma in the skin caused by early multiplication of Trypanosoma cruzi (Chagas' disease).

Chancre : The primary lesion of syphilis; typically dull red, and insensitive with a center that erodes and ulcerates, then heals slowly over a period of 4 to 6 weeks.

Chaperonin : A protein that aids in the correct folding of other proteins and the assembly of multisubunit structures.

Chaperone : A protein that affects the folding of other proteins or the assembly of complex structures.

Charcot-Leyden crystals : Slender crystals shaped like a double pyramid with pointed ends, formed from the breakdown products of eosinophils and found in feces, sputum, and tissues

Chemiosmosis : The use of ion gradients across membranes, especially proton gradients, to generate ATP. See proton motive force.

Chemolithotroph : An organism that relies on chemical compounds for energy and uses inorganic compounds as a source of electrons. (Contrast with chemoorganotroph.).

Chemiluminescence Assays (CIA) , including a subcategory using bioluminescence (biologically derived chemiluminescence agents), use the generation of light from oxidative chemical reactions as an indicator of the quantity of unbound luminescently labeled antigen. This allows quantitation of unlabeled antigen from patient specimens in a variety of homogenous (single phase) or heterogeneous (multiple phase) immunoassay techniques.

Chemoorganotroph : An organism that relies on chemical compounds for energy and uses organic compounds as a source of electrons. (Contrast with chemolithotroph.).

Chemoprophylaxis :The administration of a chemical, including antibiotics, to prevent the development of an infection or the progression of an infection to active manifest disease, or to eliminate the carriage of a specific infectious agent to prevent transmission and disease in others. Chemotherapy, on the other hand, refers to use of a chemical to treat a clinically manifest disease or to limit its further progress.

Chemostat : A continuous culture device controlled by the concentration of limiting nutrient and dilution rate.

Chemotaxis : Movement toward or away from a chemical.

Chemotherapeutic : Chemical agent used in the treatment of infections (e.g., sulfonamides).

Chemotherapy : Treatment of infectious disease with chemicals or antibiotics.

Chemotroph :An organism that uses chemical compounds energy. (Contrast with phototroph.).

Chiclero ulcer :Single, self-limiting cutaneous papule, nodule, or ulcer (usually on the face or ears) (leishmaniasis).

Chlamydoconidium :An enlarged, rounded conidium that is think walled and contains stored food, enabling it to function as a survival propagule. It may be located at the end of the hypha (terminal) or inserted along the hypha (intercalary), singly or in chains. Characteristically, it is greater in diameter than the hypha on which it is borne. Unlike other conidia, it does not readily separate from the hypha.

Chlamydospore : The misnomer applied to the thick-walled vesicle formed by Candida albicans. It neither germinates nor produces conidia when mature.

Chlorobium vesicles : Intracellular oval bodies that contain photosynthetic pigments and that underlie and are attached to the cytoplasmic membrane. Occur in Chlorobium, a genus of photosynthetic bacteria.

Chlorination : A highly effective disinfectant procedure for drinking water using chlorine gas or other chlorine-containing compounds as disinfectant.

Chlorophyll : The green pigment required for photosynthesis. It consists of a light-sensitive tetrapyrrole ring with a magnesium atom in the center.

Chloroplast : The chlorophyll-containing organelle of photosynthetic eukaryotes.

Chlorosome : A cigar-shaped structure bounded by a nonunit membrane and containing the light harvesting bacteriochlorophyll in green sulfur bacteria and in Chloroflexus.

Cholangitis : Inflammation or infection of the bile ducts.

Cholecystitis : Inflammation of the gall bladder.

Cholecystectomy : Surgical removal of the gall bladder.

Cholesterol : A type of sterol occurring widely in animal tissues as well as in some higher plants and algae. Cholesterol is notorious yet important. It is infamous among the public because of its link between the elevated serum cholesterol level and the cardiovascular disease; it is important because cholesterol is the precursor for some very important steroids such as bile acids and hormones.

Chorioamnionitis : Inflammation or infection of the chorion, amnion, amnionic fluid, and often the placental villi and decidua as well.

Chorioretinitis : Inflammation of the posterior coat and retina of the eye (toxoplasmosis).

Chromatin :Deep-staining DNA-containing portion of the nucleus (protozoa).

Chromatoidal bar/body : Deep-staining, bar-shaped, round, or splinter-shaped inclusions found in the cytoplasm of certain amebae (Entamoeba spp.).

Chromatography : Method of chemical analysis by which a mixture of substances is separated by fractional extraction or adsorption or ion exchange on a porous solid.

Chromogen : Bacterial species whose colonial growth is pigmented (e.g., Flavobacterium species, yellow).

Chromogenic : Giving rise to color, as chromogenic substrates for colored products of biochemical reactions or chromogenic bacteria that produce pigmented colonies.

Chromosome : A genetic element carrying genes essential to cellular metabolism. Prokayrotes typically have a single chromosome, consisting of a circular DNA molecule. Eukaryotic cells contain several chromosomes, each containing a linear DNA molecule complex with specific proteins.

Chronic : Longer-term infection.

Chyluria : The presence of lymph and emulsified fat in the urine (filariasis).

CIA : Chemiluminescence assays.

CIE : Counterimmunoelectrophoresis.

Cilia :Small, hairlike cytoplasmic projections from a cell or organism; used for motility (Balantidium coli).

Cilium (plural cilia) : Threadlike appendages that extend from the surface of some protozoa that beat rhythmically to propel them; cilia are membrane-bound cylinders with a complex internal array of microtubules, usually in a 9+2 pattern. Compare with flagella.

Cirrhosis : Disruption of normal structure of the liver; destruction of liver cells and increase in connective tissue (schistosomiasis).

Cl : Chlorine.

CLCR : Creatinin clearance.

Clamp Connection : A specialized bridge over a hyphal septum in the Basidiomycetes. During the formation of a new cell, it allows postmitosis nuclear migration.

Classification : The arrangement of organisms into groups based on mutual similarity or evolutionary relatedness.

Clavate :Club-shaped.

CLBs : Organisms thought to be a new pathogen, possibly an oocyst, a flagellate, an unsporulated coccidian, a large Cryptosporidium sp., a blue-green alga (cyanobacterium-like body), or a coccidian-like body, and now thought to be coccidia in the genus Cyclospora.

Cleistothecium : A large, fairly round, closed, many-celled structure in which asci and ascospores are formed and held until the structure bursts.

Clonal selection : A theory that each B or T lymphocyte, when stimulated by antigen, divides to form a clone of itself.

Clone : Group of microorganisms of identical genetic makeup derived from a single common ancestor.

Cloning vector : A DNA molecule that is able to bring about the replication of foreign DNA fragments.

Clostridium -like : A term used to describe relatively large, rectangular-shaped, anaerobic, gram-positive bacilli that may or may not be sporulating. However, some species of Clostridium do not fit this description. These species would, therefore, not be Clostridium-like in appearance.

cm : Centimeter.

CMI : Cell-mediated immunity.

CMV : Cytomegalovirus.

CNS : Central Nervous system.

CoA : Coagglutination.

CO2 : Carbon dioxide.

Coagglutination (CoA) , is similar to the Latex Agglutination (LA) technique for detecting antigen. Protein A, a uniformly distributed cell wall component of Staphylococcus aureus, is able to bind to the Fc region of most IgG isotype antibodies leaving the Fab region free to interact with antigens present in the applied specimens. The visible agglutination of the S. aureus particles indicates the antigen-antibody reaction.

Coccobacillus (plural : coccobacilli): A bacterium with a shape intermediate between coccus and bacillus.

Coccoid : Round, resembling a coccus.

Coccus (plural : cocci): A bacterium with a rounded or spherical shape.

Codon : A sequence of three purine and/or pyrimidine bases in mRNA that encodes a specific amino acid.

Coenocytic : Hyphae with many nuclei and few or no septa. Example: hyphae of Rhizopus.

Coenurus :Tapeworm larva of the genus Multiceps characterized by multiple scolices invaginated into the fluid-filled bladder; no daughter cysts produced.

Coenzyme : A low-molecular-weight chemical which participates in an enzymatic reaction by accepting and donating electrons or functional groups. Examples

Coliform : Gram-negative, nonsporing, facultative rods that ferment lactose with gas formation within 48 hours at 35 degrees C. Examples of coliform bacteria are members in the genera Escherichia (e.g. E. coli), Klebsiella (e.g. K. pneumoniae), Enterobacter (e.g. E. cloacae), and Citrobacter (e.g. C. ferundii).

Colistin : An antibiotic used in the presumptive identification of anaerobic bacteria.

Colitis :Inflammation of mucosa of colon.

Colon :Macroscopically visible growth of a microorganism on a solid culture medium.

Colonization : Multiplication of a microorganism after it has attached to host tissues or other surfaces.

Colony 1 : A clone of bacterial cells on a solid medium that is visible to the naked eye.

Colony 2 : A macroscopically visible population of cells growing on solid medium, arising from a single cell.

Colony-forming unit : Any entity (usually a viable single cell) which can form a colony on an agar plate.

Colorimetry : Chemical analysis by color determination.

Columella : The enlarged, domeshaped tip of a sporangiophore that extends into the sporangium. Often the sporangium bursts, leaving the columella bare and readily visible upon microscopic examination.

Coma : Absolute unconsciousness.

Cometabolism : The metabolic transformation of a substance while a second substance serves as primary energy or carbon source.

Commensal : Microorganism living on or in a host but causing the host no harm.

Commensalism : Association in which one individual receives benefits and the other is neither helped nor harmed.

Commodity chemical : Chemicals such as ethanol that have low monetary value and are thus sold primarily in bulk.

Common-source epidemic : An epidemic resulting from infection of a large number of people from a single contaminated source.

Communicable disease : An illness due to a specific infectious agent or its toxic products that arises through transmission of that agent or its products from an infected person, animal or inanimate reservoir to a susceptible host; either directly or indirectly through an intermediate plant or animal host, vector or the inanimate environment. (Synonym

Communicable period : The time during which an infectious agent may be transferred directly or indirectly from an infected person to another person, from an infected animal to humans, or from an infected person to animals, including arthropods.

Compatible solute : An organic compound which serves as a cytoplasmic solute to balance water relations for cells growing in environments of high salt or sugar.

Competence : Ability to take up DNA and become genetically transformed.

Complement : A complex of proteins in the blood serum that interacts sequentially with specific antibody in certain kinds of antigen-antibody reactions.

Complement fixation : The consumption of complement by an antibody-antigen reaction.

Complement fixation test : Antigen-antibody test based on fixation of complement in the presence of both elements and use of an indicator system to determine whether or not complement has been fixed.

Complementary : Nucleic acid sequences that can base pair with each other.

Complex medium : A medium whose precise chemical composition is unknown. Also called undefined medium. Compare with defined medium.

Concatamer : A DNA molecule consisting of two or more separate molecules linked end-to-end to form a long linear structure.

Concentration techniques : Procedures, usually in fecal examinations, allowing the examination of large amounts of feces (flotation or sedimentation procedures; some available for blood specimens and urine specimens).

Congenital : Existing before or at birth.

Conidiogenous cell : The cell that produces the conidia.

Conidiophore : A specialized aerial hyphal structure that serves as a stalk on which conidia are formed. The shape and arrangement of the conidiophores and the conidia are generally characteristic of a genus. The suffix, -phore, means "carrying" and is added to the word that denotes what it is carrying, e.g., conidiophores bear conidia and sporangiophores bear sporangia.

Conidiospore : An asexual spore produced in a chain from a condiophore.

Conidium (pl. conidia) :Asexual propagule that forms on the side or the end of the hypha or conidiophore. It may consist of one ore more cells, and the size, shape, and arrangement in groups are generally characteristic of the organism. It is always borne externally, i.e., not enclosed within a saclike structure such as a sporangium. If a fungus produces two types of conidia, those that are small and usually single celled are refereed to as microconidia , whereas the larger macroconidia are usually segmented into two or more cells.

Conjugation : Passing genetic information between bacteria by transferring chromosomal material, often via pili.

Conjugative plasmid : Self-transmissible plasmid; a plasmid which encodes all the functions needed for its own intercellular transmission by conjugation.

Conjunctivitis : Inflammation of the conjunctivae or membranes of the eye and eyelid.

Consensus sequence : A nucleic acid sequence in which the base present in a given position is that base most commonly found when many experimentally determined sequences are compared.

Consortium : A two (or more) membered bacterial culture (or natural assemblage) in which each organism benefits from the other.

Contact : A person or animal that has been in such association with an infected person or animal or a contaminated environment as to have had an opportunity to acquire the infection.

Contagious : Of a disease, transmissible.

Contamination : The presence of an infectious agent on a body surface, in clothes, bedding, toys, surgical instruments or dressings, or other inanimate articles or substances including water and food.

Convalescence : The period of time after a disease process has ended but before the return of optimal health is complete.

Convalescent serum :Serum collected later in the course of an illness than the acute serum, usually at least 2 weeks after initial collection.

Convulsion : A violent, involuntary contraction of an extensive group of muscles; disturbance of cerebral function (spider, scorpion envenomation).

Copy number : The number of copies of a plasmid per cell; also used to refer to the number of copies of a gene (e.g., gene copy number).

Coracidium : A ciliated larval tapeworm stage that occurs in the eggs of cestodes such as Diphyllobothrium and Spirometra spp. (pseudophyllidian tapeworms); this is a free-swimming stage, containing six hooks like those found in the oncospheres of other tapeworms.

Coremium (pl. coremia) : A cluster of erect conidiophores cemented together producing conidia at the apeces.

Cor pulmonale : Cardiopulmonary problems which may terminate in congestive heart failure; obstructive vascular disease (Schistosoma mansoni infection).

Cortex : The region inside the spore coat of an endospore around the core.

Coryza : Acuter inflammation or infection of the nasal membranes, leading to a thin watery discharge from the nose, as is seen with the common cold.

Costrovertebral angle : The area in the back where the last ribs join to their respective vertebrae.

Counterimmunoelectrophoresis (CIE) , is a procedure in which oppositely charged antigen and antibody are propelled toward each other by an electrical field. This reduces the time necessary for visualization of the antigen-antibody reaction from 18-24 hours in Immunodiffusion (ID) to less than one hour and also substantially increases the sensitivity of the analysis. CIE has the capacity of detecting concentrations of antigen/antibody 10 times smaller than the lowest concentrations measurable by Double Diffusion (DD) or ID.

Covalent : A nonionic chemical bond formed by a sharing of electrons between two atoms.

CP :Plasma concentration.

CPC : Clinical pathologic conference.

CPE : Cytopathogenic (cytopathic) effect; visual effect of virus infection on cell culture.

CPK : Creatine phosphokinase.

Crs : Serum creatinine.

Creeping eruption : Penetration and migration through subcutaneous tissues by skin-penetrating nematodes, resulting in intense pruritus and sometimes secondary bacterial or fungal infections (Strongyloides and hookworm infections, cutaneous larva migrans).

Crepitant : Relating to the crackling sound (resembling the sound that occurs when rubbing hair between the fingers) that is herad in certain disease states.

Creutzfeldt-Jakob disease (CIE) : Debilitation prion-caused disease characterized by dementia, ataxia, delirium, stupor, coma, and death: has been transmitted by organ transplant.

Crista : Inner membrane in a mitochondrion, site of respiration.

Crithidia : Old term for epimastigote.

Croup : Inflammation of upper airways (larynx, trachea) with respiratory obstruction, often caused by virus infections in children.

CRP : C-reactive protein.

Cryptosporidiosis : Intestinal infection caused by coccidia (Cryptosporidium parvum).

CSF : Cerebrospinal fluid.

CSM : Cerebrospinal meningitis.

CT : Computed tomography.

Culdocentesis : Aspiration of fluid from the cul-de-sac by puncture of the vaginal vault.

Culture : A particular strain or kind of organism growing in a laboratory medium.

Curved : Bent without angles. The term does not necessarily imply a vibrioid or helical shape but may also apply to cells curved in only one plane.

Cusingoid body habitus :An increase in adipose tissue (fat) in certain areas of the body, legs, and trunk. Purplish stripes, especially on the abdomen (striae), are also seen associated with Cushing"s disease.

Cutaneous : Pertaining to the skin.

Cuticle :Outermost, three-layered portion of the body wall of nematodes (Ascaris lumbricoides, etc.). Cyanobacterium: A prokaryotic oxygenic phototrophic bacterium containing chlorophyll a and phycobilins.

Cyanobacterium : A prokaryotic oxygenic phototrophic bacterium containing chlorophyll and phycobilins.

Cyclic photophosphorylation : The formation of ATP when light energy is used to move electrons cyclically through an electron transport chain during photosynthesis; only photosystem I participates.

Cycloheximide : An antibiotic (proprietary name, Actidione; Upjohn Co., Kalamazoo, Mich.) used in selective mycology media to inhibit the growth of saprophytic fungi. Because it is also known to inhibit some pathogenic fungi, it must be used in conjunction with a medium without antibiotics.

Cyclospora cayetanensis : Cyclospora cayetanensis is an acid-fast, coccidian-like, parasitic protozoa with the size of 8-10 micrometer in diameter. Cyclospora cayetanesis was recently recognized as a new (intestinal) protozoan pathogen of human (1993, species name was proposed in 1994) and was identified as the cause of the prolonged diarrhea of travelers as well as immunocompetent and immunocompromised patients.

Cycloserine-Cefoxitin-Fructose Agar (CCFA) : Fecal specimens thought to contain Clostridium difficile should be inoculated onto this medium. CCFA is a selective and differential medium, on which Clostridium difficile will produce yellow colonies with a ground-glass appearance, and turn the surrounding agar yellow.

CYE :Charcoal yeast extract (agar plate).

Cyst : A resting stage formed by some bacteria and protozoa in which the whole cell is surrounded by a protective layer; not the same as spore.

Cysticercoid :Tapeworm larval stage of Hymenolepis spp. and Dipylidium caninum that occurs in arthropod intermediate hosts.

Cysticercosis : Tissue infection with larval tapeworms in which the scolex is inverted into a fluid-filled bladder (Taenia solium).

Cysticercus : Tapeworm larva of the family Taeniidae (includes Taenia solium and T. saginata) in which a single scolex is invaginated into a fluid-filled bladder.

Cystitis : Inflammation of urinary bladder, most often caused by bacterial infection.

Cystocele : A hernia of the bladder; the hernia usually protrudes into the vagina.

Cytochrome :One of various iron-porphyrins that can undergo reversible oxidation-reduction and that serves as an electron carrier in an electron transport chain.

Cytologic : Relating to the study of cytology (the anatomy, physiology, pathology, and chemistry of the cell).

Cytopathic effect (CPE) :Alteration in cell morphology resulting from viral infection of a cell culture monolayer.

Cytoplasm : The protoplasm of a cell exclusive of the nuclear material.

Cytoplasmic membrane : The selectively permeable membrane surrounding the cell's cytoplasm; also called cell membrane or plasma membrane.

Cytotoxin :Toxin that produces cytopathic effects in vivo or in a tissue culture system.