Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «C»:
Cell, delta (pancreatic)
Cell, delta (pancreatic): A type of cell in the
pancreas (the organ of the
digestive system located behind the stomach). Within the
pancreas, the delta
cells are located in areas called the islets of Langerhans.
The delta cells
make somatostatin, a hormone that inhibits the release of
Cell, fat: A cell containing fat. Also called an adipocyte.
A fat cell, or adipocyte, is a connective tissue cell that has differentiated and become specialized in the synthesis (manufacture) and storage of fat.
The fat cell (adipocyte) is important to the body in maintaining proper energy balance,...
Cell, helper: A type of T cell that participates in the immune response by recognizing foreign antigens and secreting substances called cytokines that activate T and B cells. Helper cells fall into two main classes: those that activate other T cells to achieve cellular inflammatory responses; and th...
Cell, plasma: A type of white blood cell that produces and secretes antibodies. A plasma cell is a fully differentiated lymphocyte in the B-cell (not the T-cell) lineage.
As with most cell types, plasma cells can mutate to give rise to cancer. Plasma cell malignancies include multiple myeloma, Walde...
Cell, rod: A type of specialized light-sensitive cell (photoreceptor) in the retina of the eye that provides side vision and the ability to see objects in dim light (night vision).
By contrast, the cones are the retinal photoreceptors that provide sharp central vision and color vision....
Cell, somatic: See: Somatic cell....
Cell, stem: An ancestral cell, the most primitive type of cell.
Stem cells are relatively unspecialized (undifferentiated) cells that are characteristically of the same family type (lineage). They retain the ability to divide throughout life and give rise to cells that can become highly specialized...
Cell, T: See T cell....
Cell, T-4: A type of T cell that has CD4 markers on its surface and participates in the immune response by recognizing foreign antigens and secreting substances called cytokines that activate T and B cells. T-helper cells fall into two main classes: those that activate other T cells to achieve cell...
Cell, T-helper: See: T-helper cell....
Cell, totipotent: A cell with the capacity to form an entire organism.
Human development begins when a sperm fertilizes an egg and creates a single totipotent cell. In the first hours after fertilization, this cell divides into identical totipotent cells. Approximately four days after fertilizatio...
Cellophane maculopathy: See: Macular pucker....
Cells, germ: The eggs and sperm are the germ cells: the reproductive cells. Each mature germ cell is haploid in that it has a single set of 23 chromosomes containing half the usual amount of DNA and half the usual number of genes.
Except for the eggs and sperm, each cell in the human body -- there a...
Cells, reproductive: The eggs and sperm are the
reproductive cells. Each mature reproductive cell is haploid in that
it has a single set of 23 chromosomes containing half the usual
amount of DNA.
Except for the eggs and sperm, each cell in the human body --
there are 100 trillion cells in each of...
Cellulite: Popular term for deposits of fat in skin that causes a cottage cheese-like or puckered texture. Medically, cellulite is not considered abnormal. Cellulite is much more common in women than in men because of differences in the way fat, muscle, and connective tissue are distributed in men a...