C
- C terminus (C-terminal)
- Synonym for carboxy terminus. The end of a polypeptide that carries a free carboxyl (COOH) group. The last amino acid in a peptide or protein is called the carboxy terminal or C-terminal amino acid.
- calcitonin
- A protein hormone produced by cells in the thyroid gland which participates in control of calcium and phosphorus metabolism.
- calcitriol
- Another name for vitamin D.
- calcium-sensing receptor
- A membrane protein that serves as a sensor for extracellular calcium concentration.
- calorie
- (abbreviated cal) The amount of heat energy required to raise the temperature of 1 gram of water 1 degree C. This is equivalent to the amount of heat energy released by 1 gram of water when it cools by 1 degree C. A "Calorie" (capital C) is a term used especially by nutritionists and is the same as 1000 calories (1 kcal).
- canaliculus
- A very small tubular channel. Most commonly applied to channels in the liver that collect bile and deliver it to bile ducts.
- canine
- Pertaining to dogs and their relatives.
- capacitation
- Changes in the sperm that prepare it for fertilization.
- caprine
- Pertaining to goats.
- carbonic anhydrase
- Enzymes that catalyze the hydration of carbon dioxide and the dehydration of bicarbonate. Critical for such processes as production of gastric acid.
- carboxy terminus (carboxy terminal)
- The end of a polypeptide that carries a free carboxyl (COOH) group. The last amino acid in a peptide or protein is called the carboxy terminal or C-terminal amino acid.
- cardiac
- Pertaining to the heart.
- carnivore
- An animal that eats other animals. Examples include wolves, lions and spiders.
- caruncle
- Areas in the uterus of ruminants that form the maternal part of the placenta.
- catabolism (catabolic)
- The process by which organisms break down substances into simpler forms. The opposite of anabolism.
- catecholamine
- A group of compounds which include dopamine, epinephrine and norepinephrine which are used to mediate signalling in the sympathetic nervous system. They are synthesized and secreted from sympathetic neurons and the adrenal medulla.
- cecum
- A blind-ended section of the large intestine. In humans, it is adorned with the appendix.
- cellulases
- A group of enzymes that hydrolyze cellulose. Vertebrate cells do not synthesize cellulases, but microbes in the digestive tract do, allowing herbivores to take advantage of cellulose as an energy source.
- cellulose
- A structural polysaccharide of plants composed of linear chains of glucose. Present in the diet of man and many animals.
- cementum
- Bone-like material covering the root of a tooth and assisting in tooth support.
- centric fusion
- A type of translocation in which the centromeres of two acrocentric chromosomes fuse to generate one large metacentric chromosome
- chief cell
- Name given to the cell type in the lining of the stomach that secretes pepsinogen and to the cell type in the parathyroid gland that secretes parathyroid hormone.
- chimera (chimerism)
- In genetics, an animal that has more than one genetically-distinct populations of cells derived from a more than one zygote. Derived experimentally by aggregation or mixing of multiple early embryos or naturally by such processes as exchange of blood between twin fetuses.
- chole-
- Pertaining the the biliary system (gallbladder and bile ducts).
- cholecalciferol
- Another name for vitamin D.
- cholecystokinin
- A peptide hormone secreted by cells in the small intestine that stimulates contraction of the gallbladder and secretion of digestive enzymes from the pancreas.
- cholelithiasis
- The presence or formation of gallstones.
- chromaffin cells
- The predominant cell type in the medulla of the adrenal gland; secretes the hormones epinephrine and norepinephrine.
- chronic
- Persisting over a long period of time.
- chylo
- Referring to lymph.
- chylomicron
- A package of lipids synthesized in small intestinal epithelial cells and delivered into intestinal lymphatic vessels. Consists of triglycerides, cholesterol and lipoproteins.
- chyme
- The liquified foodstuffs generated by digestion in the stomach which flow into the small intestine.
- chymosin
- An enzyme secreted into the lumen of the stomach of young animals that coagulates milk. Also known as rennin.
- chymotrypsin
- A proteolytic enzyme that digests proteins into peptides. Produced in abundance by the pancreas.
- CIP
- An acronym for calf intestinal phosphatase, which is used in the laboratory to dephosphorylate DNA.
- circadian
- Pertaining to a period of a day. Ciradian rhythms are events that repeat at about the same time each day.
- cleavage
- Multiple definitions. To embryologists, cleavage refers to stages in the development of embryos, when then go from one-cell to two-cell to four-cell embryos and so on.
- cloaca
- An expanded, tubular structure that serves as the common opening of the digestive, reproductive and urinary systems in many vertebrates, including birds.
- colloid
- A proteinaceous product of thyroid epithelial cells composed mostly of thyroglobulin.
- colon
- A section of the large intestine.
- congenital
- Present at birth, as in a congenital defect. This term says nothing about cause and is not equivalent to "genetic".
- contra-
- Prefix meaning against. A contraceptive is something that works against conception.
- coprophagy
- Eating feces, a behavior seen especially in rodents and rabbits; thought to have evolved to conserve water-soluble vitamins.
- cortical granules
- Lysosome-like granules in the mature ovum that participate in fertilization.
- corticosteroid
- Another name for a glucocorticoid. A type of steroid hormone synthesized and secreted from the adrenal cortex.
- corticosterone
- A steroid hormone similar to cortisol produced by the adrenal cortex that participates in control of blood glucose concentration as well as several other processes. The major glucocorticoid in rodents.
- corticotropin
- Another name for adrenocorticotropic hormone - a peptide hormone secreted from the anterior pituitary that stimulates secretion of glucocorticoids from the adrenal glands.
- corticotropin-releasing hormone
- A peptide hormone secreted by the hypothalamus that stimulates secretion of adrenocorticotropic hormone from the anterior pituitary gland.
- cortisol
- A steroid hormone produced by the adrenal cortex that participates in control of blood glucose concentration as well as several other processes.
- cotyledon
- The fetal portion of the placenta in animals such as cattle and sheep.
- cretinism
- A syndrome of growth and mental retardation in young children due to congenital deficiency in thyroid hormones.
- crypts of Lieberkuhn
- Small infoldings of the small intestinal mucosa which surround villi. Also seen without villi in the large intestine.
- Cushings disease
- An endocrine disease also called hyperadrenocorticism, resulting from an excess of glucocorticoids (cortisol).
- cyclic AMP
- Cyclic 3'-5' adenosine monophosphate - a nucleotide derived from ATP thorough the action of adenylyl cyclase. Used as a second messenger by a number of hormones.
- cyclic AMP-dependent protein kinase
- An enzyme that modifies proteins by addition of phosphate groups to specific amino acids; its activity is regulated by cyclic AMP. Also known as the protein kinase A.
- cystic duct
- A section of the biliary system that conveys bile into the gall bladder.
- cytogenetics
- The study of normal and abnormal chromosomes.
- cytology
- The study of cells, their origin, structure and function. In medicine, often used to describe the study and identification of cells from clinical specimens.
- cytology, vaginal
- The study of vaginal epithelial cells, which is commonly used to monitor the state of reproduction in animals like dogs.
Last updated on 10/2/2004