Biotechnology and Genetics terms starting with C

393 terms

Central Line A central line is a flexible tube that is inserted near a patient's heart or into one of the large blood vessels near the heart.
central mother cell A subsurface cell located in a plant apical meristem and characterized by a large vacuole.
centre of origin The geographic locations where a particular domesticated plant species originated.
Centrifugation Separating molecules by size or density using centrifugal forces generated by a spinning rotor.
centrifuge A mechanical device which delivers the centrifugal forces necessary for centrifugation.
centriole An organelle in many animal cells that appears to be involved in the formation of the spindle during mitosis.
Centromere The central portion of the chromosome to which the spindle fibers attach during mitotic and meiotic division.
centrosome A specialized region of a living cell, situated next to the nucleus, where microtubules are assembled and broken down during cell division.
cephem-type antibiotic An antibiotic that shares the basic chemical structure of cephalosporin.
Cerebrospinal fluid (seh-REE-broh-SPY-nul...) The fluid that flows in and around the hollow spaces of the brain and spinal cord, and between two of the meninges (the thin…
chain terminator 1. See: stop codon. 2. In the Sanger method of DNA sequencing, refers to the labelled di-deoxynucleotide triphosphates which are added to disrupt DNA…
Chakrabarty decision A landmark legal case in the U.S.A., in which it was held that the inventor of a new micro-organism whose invention otherwise met the legal requirements…
chaperone A family of proteins that ensure the correct assembly and conformation of other polypeptides in vivo as they emerge from the ribosome, but are not…
chaperonin See: chaperone.
character See: trait.
Characterization Description of the essential properties of an organism or system.
Charcoal The black porous residue of partly burnt wood, bones, etc; a form of carbon. See: activated charcoal
chelate A cation bound to an organic molecule through electron pair donation from nitrogen and/or oxygen atoms in its structure.
chemical mutagen A chemical capable of inducing mutations in living organisms.
chemically-defined medium When all of the chemical components of a culture medium are fully known and defined.
chemiluminescence The emission of light during the course of a chemical reaction.
chemostat A continuous and open culture in which growth rate and cell density are maintained constant by a fixed rate of input of a growth-limiting nutrient.
chemotaxis The movement of a cell, or the whole or part of an organism, towards or away from an increasing concentration of a particular substance.
Chemotherapy (KEE-moh-THAYR-uh-pee) Treatment with drugs that kill cancer cells.
chiasma (ki-AZ-ma) An anatomy term for an X-shaped crossing (for example, of nerves or tendons).
Chimera (or chimaera) 1. An organism whose cells are not all genotypically identical. This can occur as a result of: somatic mutation; grafting (see: graft…
Chimera (pl. chimaera) An organism that contains cells or tissues with a different genotype. These can be mutated cells of the host organism or cells from a different organism…
Chimeraplasty A method designed to create defined alterations in DNA sequence at a target locus, with potential both for gene therapy and for investigating gene…
chimeric DNA See: chimera (2).
chimeric gene An engineered gene, where a coding sequence is fused to promoter and/or other sequences derived from a different gene.
chimeric protein See: fusion protein.
chimeric selectable marker gene A gene that is constructed from parts of two or more different genes and allows the host cell to survive under conditions where it would otherwise die.
chip See: micro-array.
chitin A type of polysaccharide (sugar molecule) that is made by some plants and animals.
chitinase An enzyme which breaks down chitin.
Chloramphenicol An antibiotic that interferes with protein synthesis.
chlorenchyma Plant tissue (leaf mesophyll and other parenchyma cells) containing chloroplasts.
chlorophyll One of the two pigments responsible for the green colour of most plants. It is an essential component of the machinery to absorb light energy for…
chloroplast Specialized plastid that contains chlorophyll. Lens-shaped and bounded by a double membrane, chloroplasts contain membranous structures (thylakoids) piled…
Chloroplast chromosome Circular DNA found in the photosynthesizing organelle (chloroplast) of plants instead of the cell nucleus where most genetic material is located.
chloroplast DNA The DNA present in the chloroplast. Although the chloroplast has a small genome, the large number of chloroplasts per cell ensures that chloroplast DNA is…
chloroplast transit peptide (Abbreviation: CTP). A transit peptide that, when fused to a protein, acts to transport that protein into plant chloroplasts.
chlorosis The appearance of yellow colour in plants, due to the failure of development or the breakdown of chlorophyll.
Chondrocytes Cartilage cells.
Chorion The multilayered, outermost fetal membrane. As pregnancy progresses, part of the chorion becomes the placenta.
Chromatid Each of the two daughter strands of a duplicated chromosome joined at the centromere during mitosis and meiosis.
chromatin Substance of which eukaryotic chromosomes are composed. It consists of a complex of DNA, histone and non-histone chromosomal proteins (mainly histones)…
chromatin fibre The standard structural conformation of chromatin in strands of 30 nm average diameter.
Chromatography a method for separating mixtures based on differences in the speed at which they migrate over or through a stationary phase.
chromocentre Body produced by fusion of the heterochromatic regions of the chromosomes in the polytene tissues (e.g. the salivary glands) of certain Diptera.
chromogenic substrate A compound or substance that contains a colour-forming group.
Chromomere One of the serially aligned beads or granules of a eukaryotic chromosome, resulting from local coiling of a continuous DNA thread.
chromomeres Small dense bodies identified by their characteristic size and linear arrangement along a chromosome.
chromonema (pl.: chromonemata) An optically single thread forming an axial structure within each chromosome.
chromoplast Plastid containing pigments other than chlorophyll. See: chloroplast.
chromosomal aberration An abnormal change in chromosome structure or number, including deficiency, duplication, inversion, translocation, aneuploidy, polyploidy, or any other…
Chromosomal deletion The loss of part of a chromosome's DNA.
chromosomal integration site A chromosomal location where foreign DNA can be integrated, often without impairing any essential function in the host organism.
Chromosomal inversion Chromosome segments that have been turned 180 degrees. The gene sequence for the segment is reversed with respect to the rest of the chromosome.
chromosomal polymorphism The occurrence of one to several chromosomes in two or more alteRNA tive structural forms within a population; the structurally changed chromosomes are…
Chromosome (KROH-muh-some) Part of a cell that contains genetic information. Except for sperm and eggs, all human cells contain 46 chromosomes.
chromosome aberration See: chromosomal aberration.
chromosome banding Differential staining of chromosomes in such a way that light and dark areas occur along the length of the chromosomes in repeatable patterns.
chromosome jumping A technique that allows two segments of duplex DNA that are separated by thousands of base pairs (about 200 kb) to be cloned together.
chromosome landing An alteRNA tive to chromosome walking for positional cloning. Clones of genomic DNA are fragmented so as to include both the target gene and a closely…
chromosome mutation A change in the gross structure of a chromosome, usually causing severely deleterious effects in the organism, but can be maintained in a population (See…
Chromosome painting Attachment of certain fluorescent dyes to targeted parts of the chromosome. Used as a diagnositic for particular diseases, e.g. types of leukemia.
Chromosome region p A designation for the short arm of a chromosome.
Chromosome region q A designation for the long arm of a chromosome.
chromosome theory of inheritance The theory that chromosomes carry the genetic information and that their behaviour during meiosis provides the physical basis for segregation and…
Chromosome walking Working from a flanking DNA marker, overlapping clones are successively identified that span a chromosomal region of interest. (See Chromosome.)
Chromosomes The self-replicating genetic structure of cells containing the cellular DNA. Humans have 23 pairs of chromosomes.
chymosin An enzyme that clots milk, used in the manufacture of cheese.
ciliate (adj.) See cilium.
cilium (pl.: cilia) Hairlike locomotor structure on certain cells; a locomotor structure on a ciliate protozoan.
circadian Of physiological activity, etc.: recurring at approximately 24-hour intervals.
circularization The self-ligation of a linear DNA fragment having complementary ends, generally generated by digestion with a restriction endonuclease.
cis configuration See: coupling.
cis heterozygote A double heterozygote that contains two mutations arranged in a cis configuration (e.g. a+ b+ / a b).
cis-acting protein A protein with the particular property of acting only on the molecule of DNA from which it was expressed.
cis-acting sequence A nucleotide sequence that only affects the expression of genes located on the same chromosome.
Cistron A DNA sequence that codes for a specific polypeptide; a gene. See DNA, Gene.
class switching The process during which a plasma cell stops producing antibodies of one class and begins producing antibodies of another class.
Cleavage The process of cell division in the very early embryo before it becomes a blastocyst.
cleave To break phosphodiester bonds of double-stranded DNA, usually with a type II restriction endonuclease. Synonyms: cut; digest.
cleaved amplified polymorphic sequence A segment of DNA that can be amplified by polymerase chain reaction (PCR) and which contains a DNA sequence polymorphism.
cline Variation in one or more phenotypic characters or allele frequencies across a geographical gradient.
clonal propagation Asexual propagation of many new plants (ramet s) from an individual (ortet ); all have the same genotype.
clonal selection The production of a population of plasma cells all producing the same antibody in response to the interaction between a B lymphocyte producing that…
Clonality A line of cells that is genetically identical to the originating cell; in this case, a stem cell.
Clone An exact genetic replica of a specific gene or an entire organism. See Cloning.
Clone bank See: gene bank.
cloned strain or line A strain or line descended directly from a clone.
Cloning The mitotic division of a progenitor cell to give rise to a population of identical daughter cells or clones.
cloning site See: insertion site.
Cloning vector A small, self-replicating DNA molecule - usually a plasmid or viral DNA chromosome - into which foreign DNA is inserted in the process of cloning genes or…
cloning vehicle See: cloning vector.
closed continuous culture A culture system, in which the inflow of fresh medium is balanced by the outflow of corresponding volumes of spent medium.
Cluster differentiation (CD) Cell membrane molecules used to classify leukocytes into subsets.
cluster of differentiation See: CD molecules.