Biomaterial Database

Ultrastructure of the calcareous layer eggshell of the turtle Emys orbicularis (L.). Preliminary study. 1997

S Mitrus

Department of Comparative Anatomy, Jagiellonian University.

The calcareous layer of Emys orbicularis eggshell was examined by scanning electron microscopy. The layer is composed of well distinguished shell units which consist of needle-like crystallites radiating outwards from the cores. The linear structures of the cores on the inner surface appear to be similar to those in the eggshell of Mauremys caspica. On the inner surface of shell units of eggs with dead embryos there are flat, conical depressions. This surface in specimens from unfertilized eggs is almost flat. It may suggest that a developing embryo derives calcium from the eggshell.

UI	MeSH Term	Description	Entries
D008855	Microscopy, Electron, Scanning	Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.	Scanning Electron Microscopy,Electron Scanning Microscopy,Electron Microscopies, Scanning,Electron Microscopy, Scanning,Electron Scanning Microscopies,Microscopies, Electron Scanning,Microscopies, Scanning Electron,Microscopy, Electron Scanning,Microscopy, Scanning Electron,Scanning Electron Microscopies,Scanning Microscopies, Electron,Scanning Microscopy, Electron
D002119	Calcium Carbonate	Carbonic acid calcium salt (CaCO3). An odorless, tasteless powder or crystal that occurs in nature. It is used therapeutically as a phosphate buffer in hemodialysis patients and as a calcium supplement.	Aragonite,Calcite,Chalk,Limestone,Marble,Milk of Calcium,Vaterite,Calcium Milk,Carbonate, Calcium
D004528	Egg Shell	A hard or leathery calciferous exterior covering of an egg.	Eggshell,Egg Shells,Eggshells,Shell, Egg,Shells, Egg
D004531	Eggs	Animal reproductive bodies, or the contents thereof, used as food. The concept is differentiated from OVUM, the anatomic or physiologic entity.
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014426	Turtles	Any reptile including tortoises, fresh water, and marine species of the order Testudines with a body encased in a bony or cartilaginous shell consisting of a top (carapace) and a bottom (plastron) derived from the ribs.	Sea Turtles,Terrapins,Tortoises,Sea Turtle,Terrapin,Tortoise,Turtle,Turtle, Sea,Turtles, Sea