Canine - pertaining to dogs.

Cap - the structure found on the 5'- end of eukaryotic mRNA, and consisting of an inverted, methylated guanosine residue.

Cap site - the site in a gene where translation is initiated, a.k.a. translation initiation site.

Capacitation - the final stage in the maturation process of a spermatozoon, taking place inside the female genital tract as the sperm penetrates the ovum.

Capsid - the protein coat of a virus The capsid often determines the shape of the virus.

Carbohydrate - an organic compound based on the general formula Cx(H2O)y performing many vital roles in living organisms. The simplest carbohydrates are the sugars (saccharides), including glucose and sucrose. Polysaccharides are carbohydrates of much greater molecular weight and complexity; examples are starch, which serves as energy store in plant seeds and tubers; cellulose and lignin that form the cell walls and woody tissue of plants of plants; glycogen, etc.

Carboxypeptidases - two enzymes (A and B) found in pancreatic juice. Their role is to remove the C terminal amino-acid from a peptide; the A form removes any amino acid; the B form removes only lysine or arginine. Used when sequencing peptides.

Carcinogen - a substance capable of inducing cancer ill an organism.

Carcinoma - a malignant tumour derived. from epithelial tissue, which forms the skin and the outer cell layers of internal organs

Carotene - a reddish-orange plastid pigment involved in light reactions in photosynthesis.

Carotenoid - red to yellow pigments responsible for the characteristic colour of many plant organs or fruits, such as tomatoes, carrots, etc. Oxidation: products of carotene are. called xanthophylls. Carotenoids serve as light-harvesting molecules in photosynthetic assemblies and also playa role in protecting. prokaryotes from the deleterious effects of light.

Carpel - female reproductive organ of flowering plants, consisting of stigma, style and ovary, In some plants, one or more carpels unite to form the pistil. nbsp.

Carrier - in genetics, typically an individual that has one recessive mutant allele for some defective condition that is masked by a dominant normal allele at the same locus, i.e., an individual that is heterozygous for a recessive harmful allele and a dominant normal allele; the phenotype is normal, but the individual passes the defective (recessive) allele to half of its offspring.

Carrier DNA - DNA of undefined sequence content which is added to the transforming (plasmid) DNA used in physical DNA transfer procedures. This additional DNA increases the efficiency of transformation in electroporation and chemically mediated DNA delivery systems. The mechanism responsible for this effect is not known. See also binary vector; plasmid; chimeric gene.

Carrier gas - the gas that carries the sample in gas chromatography.

Casein - a group of proteins found in milk.

Casein hydrolysate - mixture of amino acids and peptides produced by enzymatic or acid hydrolysis of casein. cf organic complex; undefined.

Catabolic pathway - a pathway by which an organic molecule is degraded in order to release energy for growth and other cellular processes; degradative pathway.

Catabolism - the metabolic breakdown of large molecules in living organism, with accompanying release of energy.

Catabolite repression - glucose-mediated reduction in the rates of transcription of operons that encode enzymes: involved in catabolic pathways (such as the lac operon).

Catalysis - the process of changing the rate of a chemical reaction by : use of a catalyst.

Catalyst - a substance that promotes a chemical reaction by lowering the activation energy of a chemical reaction, without itself undergoing any permanent chemical change. The process is catalysis. if catalytic antibody; catalytic RNA.

Catalytic antibody - an antibody selected for its ability to catalyse a chemical reaction by binding to and stabilising the transition state intermediate.

CDNA - the double stranded DNA complement of an mRNA sequence; synthesised in vitro from a mature RNA template using reverse transcriptase (to create a single strand of DNA from the RNA template) and DNA polymerase (to create the double-stranded DNA). Preparation of cDNAs is often the first step in cloning DNA sequences of interest. Used as specific and sensitive probes in hybridisation studies, because cDNAs usually do not include regulatory or other controlling sequences, and so they can be used to identify (probe) and isolate genes and their associated sequences from genomic DNA.