biology-dictionary_11-06-2009

Codon A three-nucleotide sequence of DNA or mRNA that specifies a particular amino acid or termination signal; the basic unit of ...

Cold aclimation response The process by which plants increase their tolerance to freezing by exposure to low, nonfreezing temper ...

Commensalism A symbiotic relationship in which the symbiont benefits but the host is neither helped nor harmed. Community All th ...

Complete digestive tract A digestive tube that runs between a mouth and an anus; also called alimentary canal. An incomplete dig ...

Cone cell (1) In plants, the reproductive structure of a conifer. (2) In vertebrates, a type of photoreceptor cell in the retina ...

Continuous fibers A material consisting of extremely fine glass fibers, used in making various products, such as yarns, fabrics, ...

Cork cambium A cylinder of meristematic tissue in plants that produces cork cells to replace the epidermis during secondary grow ...

Coupled reactions In cells, the linking of endergonic (energy-requiring) reactions to exergonic (energy- releasing) reactions th ...

Cuboidal ciliated epithelium Cuboidal epithelia are epithelial cells having a cube-like shape; that is, their width is approxima ...

Cyclostomata A subclass comprising the simplest and most primitive of living vertebrates characterized by the absence of jaws an ...

Cytoskeleton A network of microtubules, microfilaments, and intermediate filaments that branch throughout the cytoplasm and serv ...

Dehydration reaction A chemical reaction in which two molecules covalently bond to one another with the removal of a water molec ...

Deoxyribose The sugar component of DNA, having one less hydroxyl group than ribose, the sugar component of RNA. Dependent variab ...

Determination The progressive restriction of developmental potential, causing the possible fate of each cell to become more limi ...

Dichlamydeous Having two coverings, a calyx and a corolla. Dicot A subdivision of flowering plants whose members possess two emb ...

Dipeptides A dipeptide is a molecule consisting of two amino acids joind by a single peptide bond. Diploid cell A cell containin ...

DNA Abbreviation of deoxyribonucleic acid. DNA ligase width="400" valign="TOP"> A linking enzyme essential for DNA replicatio ...

Dorsal Pertaining to or situated near the back; opposite of ventral. Dorsoventrally Relating to or involving, or extending along ...

E Ebracteate Having no bracts. Ecdysis The shedding of an outer integument or layer of skin, as by insects, crustaceans, and sna ...

Ecotype A locally adapted variant of a species, differing genetically from other ecotypes of the same species. Ectoderm The oute ...