Biomaterial Database

Fine structure of the human secretory ameloblast. 1978

M E Matthiessen, and P Römert

The fine structure of secretory ameloblasts in primary tooth germs from a human fetus was investigated. Various aldehyde fixatives produced varying qualities of preservation. The morphology of the best preserved ameloblasts differed from that earlier described, mainly in the following respects: the rough endoplasmic cisternae were lamellated and regularly arranged, the mitochondria were of regular shape and size, and the ground substance was dense and homogenous. The extensive Golgi complexes, the mitochondria and the rough endoplasmic cisternae in the apical (distal) part of the ameloblast were longitudinally arranged.

UI	MeSH Term	Description	Entries
D008928	Mitochondria	Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive RIBOSOMES, transfer RNAs (RNA, TRANSFER); AMINO ACYL T RNA SYNTHETASES; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs (RNA, MESSENGER). Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. (King & Stansfield, A Dictionary of Genetics, 4th ed)	Mitochondrial Contraction,Mitochondrion,Contraction, Mitochondrial,Contractions, Mitochondrial,Mitochondrial Contractions
D009805	Odontogenesis	The process of TOOTH formation. It is divided into several stages including: the dental lamina stage, the bud stage, the cap stage, and the bell stage. Odontogenesis includes the production of tooth enamel (AMELOGENESIS), dentin (DENTINOGENESIS), and dental cementum (CEMENTOGENESIS).	Odontogeneses
D004721	Endoplasmic Reticulum	A system of cisternae in the CYTOPLASM of many cells. In places the endoplasmic reticulum is continuous with the plasma membrane (CELL MEMBRANE) or outer membrane of the nuclear envelope. If the outer surfaces of the endoplasmic reticulum membranes are coated with ribosomes, the endoplasmic reticulum is said to be rough-surfaced (ENDOPLASMIC RETICULUM, ROUGH); otherwise it is said to be smooth-surfaced (ENDOPLASMIC RETICULUM, SMOOTH). (King & Stansfield, A Dictionary of Genetics, 4th ed)	Ergastoplasm,Reticulum, Endoplasmic
D006056	Golgi Apparatus	A stack of flattened vesicles that functions in posttranslational processing and sorting of proteins, receiving them from the rough ENDOPLASMIC RETICULUM and directing them to secretory vesicles, LYSOSOMES, or the CELL MEMBRANE. The movement of proteins takes place by transfer vesicles that bud off from the rough endoplasmic reticulum or Golgi apparatus and fuse with the Golgi, lysosomes or cell membrane. (From Glick, Glossary of Biochemistry and Molecular Biology, 1990)	Golgi Complex,Apparatus, Golgi,Complex, Golgi
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000565	Ameloblasts	Cylindrical epithelial cells in the innermost layer of the ENAMEL ORGAN. Their functions include contribution to the development of the dentinoenamel junction by the deposition of a layer of the matrix, thus producing the foundation for the prisms (the structural units of the DENTAL ENAMEL), and production of the matrix for the enamel prisms and interprismatic substance. (From Jablonski's Dictionary of Dentistry, 1992)	Ameloblast
D014083	Tooth Germ	The collective tissues from which an entire tooth is formed, including the DENTAL SAC; ENAMEL ORGAN; and DENTAL PAPILLA. (From Jablonski, Dictionary of Dentistry, 1992)	Germ, Tooth,Germs, Tooth,Tooth Germs