lamina /lam·i·na/ (lam´ĭ-nah) pl. la´minae [L.]
lamina
lamina (lam´in
),
1. layer; a thin, flat plate of a larger composite structure.
2. l. of vertebra.
basal lamina
1. the layer of the basement membrane lying next to the basal surface of the adjoining cell layer, comprising two layers, the electron-lucent lamina lucida and the electron-dense lamina densa.
2. sometimes, the entire basement membrane.
3. l. basalis.
lamina basa´lis
1. one of the pair of longitudinal zones of the embryonic neural tube, from which develop the ventral gray columns of the spinal cord and the motor centers of the brain.
2. basal l. (1).
lamina basila´ris the posterior wall of the cochlear duct, separating it from the scala tympani.
Bowman's lamina see under membrane.
lamina choroidocapilla´ris the inner layer of the choroid, composed of a single-layered network of small capillaries.
lamina cribro´sa
1. fascia cribrosa.
2. (of ethmoid bone) the horizontal plate of ethmoid bone forming the roof of the nasal cavity, and perforated by many foramina for passage of olfactory nerves.
3. (of sclera) the perforated part of the sclera through which pass the axons of the retinal ganglion cells.
lamina den´sa see basal l. (1).
elastic lamina
epithelial lamina the layer of ependymal cells covering the choroid plexus.
lamina lu´cida see basal l. (1).
nuclear lamina a tightly woven meshwork that lines the nuclear side of the inner nuclear membrane; it is believed to control the shape of the nucleus.
lamina pro´pria
1. the connective tissue layer of mucous membrane.
2. the middle fibrous layer of the tympanic membrane.
lamina ra´ra lamina lucida; see basal l. (1). In the lung alveoli and renal glomeruli, one may occur on each side of the lamina densa.
reticular lamina
1. a layer of the basement membrane, adjacent to the connective tissue, seen in some epithelia.
2. l. reticularis.
lamina reticula´ris the perforated hyaline membrane covering the organ of Corti.
Rexed's laminae , spinal laminae an architectural scheme used to classify the structure of the spinal cord, based on the cytological features of the neurons in different regions of the gray substance. 
)
Rexed's laminae in a cross section of the spinal cord at approximately the level of the seventh cervical vertebra (C7).
lamina spira´lis
1. a double plate of bone winding spirally around the modiolus, dividing the spiral canal of the cochlea into the scala tympani and scala vestibuli.
2. a bony projection on the outer wall of the cochlea in the lower part of the first turn.
terminal lamina of hypothalamus the thin plate derived from the telencephalon, forming the anterior wall of the third ventricle of the cerebrum.
lamina of vertebra , lamina of vertebral arch either of the pair of broad plates of bone flaring out from the pedicles of the vertebral arches and fusing together at the midline to complete the posterior part of the arch and provide a base for the spinous process.
lam·i·na (l m  -n)n. pl. lam·i·nas or lam·i·nae (-n   ) 1. A thin plate, sheet, or layer. 2. A thin layer of bone, membrane, or other tissue. lam i·nar, lami·nal adj. |
lamina
[lam′inə] pl. laminae
Etymology: L, thin plate
any thin, flat layer of membrane or other bulkier tissue. It may be structureless or part of a structure, as the laminae of the vertebral arch.
lamina (lam´in
),n a flat, thin plate.
lamina, dental,
n a band of epithelial tissue that connects a developing tooth bud to the oral mucosa of the oral cavity.
lamina dura,
n a radiographic term denoting the plate of compact bone (alveolar bone) that lies adjacent to the periodontal ligament.
lamina propria,
n the zone of connective tissue subjacent to the epithelium of a mucous membrane such as the
oral mucosa.
oral mucosa.
lamina
pl. laminae [L.] a thin, flat plate or layer; a layer of a composite structure. Often used alone to mean a vertebral lamina.
lamina basilaris
the posterior wall of the cochlear duct, separating it from the scala tympani.
lamina choroidocapillaris
the inner layer of the choroid, composed of a single-layered network of small capillaries.
lamina cribrosa
1. fascia cribrosa.
2. (of ethmoid bone) the sieve-like transverse plate of ethmoid bone forming the roof of the nasal cavity, and perforated by many foramina for passage of olfactory nerves.
3. (of sclera) the perforated part of the sclera through which pass the axons of the retinal ganglion cells to enter the optic nerve.
lamina densa, lamina dura
a layer of dental alveolar bone containing more than usual amounts of highly calcified cementing substance, associated with periodontal fibers in the bone; causes lines of increased radiodensity in dental radiographs—hence the name.
epithelial lamina
the layer of ependymal cells covering the choroid plexus.
lamina epithelialis mucosae
the layer of epithelial cells on the surface of the mucosa.
lamina femoralis
that part of the aponeurosis of the external abdominal oblique muscle which continues the lateral lip of the superficial inguinal ring onto the medial surface of the thigh in some species such as the horse.
lamina fibroreticularis
a thick layer of collagenous fibers projecting into the connective tissue space underlying the basement membrane.
lamina fusca
the loose connective tissue, deep, pigmentary layer of the sclera.
horny lamina
the laminae on the inside of the hoof which interdigitate with the sensitive laminae attached to the hoof corium.
lamina limitans
the layer of unmineralized matrix covering a bone surface that is not undergoing metabolic or structural change.
lamina lucida
the modified cell coat, appearing as a clear zone separating the basal lamina from the cell membrane.
lamina mucosae
includes laminae epithelialis mucosae (above), muscularis mucosae, propria mucosae (see below).
lamina muscularis mucosae
one or more smooth muscle layers, provides local mobility to the mucous membrane of organs; variable in occurrence.
omasal lamina
the leaves which line the internal aspect of the omasal wall; accounts for the colloquial name for the organ—bible; the religious connotation, if any, is unexplained.
lamina propria, lamina propria mucosae
1. the connective tissue layer of mucous membrane.
2. the middle fibrous layer of the tympanic membrane.
sensitive lamina
the laminae which interdigitate with the horny laminae of the hoof and which are made up of laminar corium plus a coat of not yet cornified epidermis.
spiral lamina, lamina spiralis
1. a double plate of bone winding spirally around the modiolus, dividing the spiral canal of the cochlea into the scala tympani and scali vestibuli.
2. a bony projection on the outer wall of the cochlea in the lower part of the first turn.
terminal lamina of hypothalamus
the thin plate derived from the telencephalon, forming the anterior wall of the third ventricle of the cerebrum.
lamina terminalis grisea
thin plate forming the rostral wall of the third ventricle.
transverse lamina
separates the caudal part of the nasal cavity of the pig and dog into a ventral respiratory part and a dorsal olfactory part.
udder suspensory lamina
see udder suspensory apparatus.
vascular lamina
the vascular layer of the choroid of the eye; it lies between the suprachoroid and the choriocapillary layer.
vertebral lamina
either of the pair of broad plates of bone flaring out from the pedicles of the vertebral arches and fusing together at the midline to complete the dorsal part of the arch and provide a base for the spinous process.
lamina
Thin sheet or layer. Example: the lamina vitrea of Bruch's membrane.
How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content.
| ?Page tools | ||
|---|---|---|
|