operculum


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operculum

 [o-per´ku-lum] (L.)
1. a lid or covering.
2. the folds of pallium from the frontal, parietal, and temporal lobes of the cerebrum overlying the insula. adj., adj oper´cular.
dental operculum the hood of gingival tissue overlying the crown of an erupting tooth.
trophoblastic operculum the plug of trophoblast that helps close the gap in the endometrium made by the implanting blastocyst.

o·per·cu·lum

, gen.

o·per·cu·li

, pl.

o·per·cu·la

(ō-per'kyū-lŭm, -lī, -lă),
1. Anything resembling a lid or cover.
2. In anatomy, the portions of the frontal (operculum frontale [TA], frontal operculum [TA]), parietal (operculum parietale [TA], parietal operculum [TA]), and temporal (operculum temporale [TA], temporal operculum [TA]) lobes bordering the lateral sulcus and covering the insula.
3. In parasitology, the lid or caplike cover of the shell opening of operculated freshwater snails in the subclass Prosobranchiata, and of the eggs of certain trematode and cestode parasites.
4. The attached flap in the tear of retinal detachment.
5. The mucosal flap partially or completely covering an unerupted tooth.
[L. cover or lid, fr. operio, pp. opertus, to cover]

operculum

(ō-pûr′kyə-ləm)
n. pl. opercu·lums or opercu·la (-lə)
1. Something resembling a lid or cover.
2. The portions of the frontal, parietal, and temporal lobes covering the insula.
3. A bit of mucus sealing the endocervical canal of the uterus after conception.
4. The attached flap in cases of torn retinal detachment.

o·per′cu·lar (-lər) adj.

o·per·cu·lum

, pl. opercula (ō-pĕr'kyū-lŭm, -lă) [TA]
1. Anything resembling a lid or cover.
2. [TA] anatomy The portions of the frontal, parietal, and temporal lobes bordering the lateral sulcus and covering the insula.
3. Mucus sealing the endocervical canal of the uterus after conception has taken place.
4. parasitology The lid or caplike cover of the shell opening of operculated freshwater snails in the subclass Prosobranchiata, and of the eggs of certain trematode and cestode parasites.
5. The attached flap in the tear of retinal detachment.
6. The mucosal flap partially or completely covering a partially erupted tooth.
[L. cover or lid, fr. operio, pp. opertus, to cover]

operculum

A covering membrane, flap or lid of tissue, especially in the brain, or over an erupting tooth.

operculum

  1. the lid of a MOSS capsule.
  2. a hard bony flap covering the gills of fishes.
  3. the plate of exoskeletal material on the foot of a gastropod mollusc with which it closes off the entrance to the shell.

operculum 

A flap of detached retina which projects forward, or is totally free in the vitreous. It can happen as a result of a retinal tear (break).

o·per·cu·lum

, pl. opercula (ō-pĕr'kyū-lŭm, -lă) [TA]
1. [TA] The mucosal flap partially or completely covering an unerupted tooth.
2. Anything resembling a lid or cover.
[L. cover or lid, fr. operio, pp. opertus, to cover]
References in periodicals archive ?
Deep location of the muscle scars in strongly coiled gastropods reflects withdrawal of the cephalopedal mass into the shell as a response to environmental stress or predation, in conjunction with the development of an operculum. In contrast, the muscle scars in the various limpet groups are arranged around the periphery, close to the apertural margin, since their defensive strategy involves clamping against the substratum rather than withdrawal into the shell; an operculum is not retained in the adult.
In the present study, we qualitatively observed various behaviors indicative of condition such as closing the operculum, secreting corporal mucus, crawling, responding to a metal needle, feeding, and stooling; and we quantitatively examined the locomotion behavior of B.
Broadly elliptical refers to a pore or operculum that is wider than high, with its long axis perpendicular to the central axis of the fruit.
In svPPA, the disconnection in the network between putamen and operculum has not been reported previously.
Drews & Sampson (1956) distinguished it from Tetralicia by the vasiform orifice which has a smooth inner margin with the operculum filling or nearly filling the orifice whereas the inner margin of the vasiform orifice of Tetralicia has teeth and the operculum fills three-fourths or less of the orifice.
Other cargo and artifacts found with the wreck were raw ivory and hippo teeth, African Blackwood logs, traces of spices and oils, Cypriot and Syrian pottery, operculum shells, used to make incense, jewelry, ostrich eggs and 24 anchor stones.
According to Thatcher (2006), specimens of the genus can be found in tongue and operculum cavity of the hosts, they have symmetric body, cephalon little immersed in pereonite 1, all seven pairs of pereopods prehensile and provided with stout claw-like dactyls and pleotelson usually wider than long.
4): seta length, costa of the internal perichaetial bracts present, operculum shape, and leaf position when dry.
Three eggs had their opercula detached and shells destroyed to allow examination and measurement of the operculum and internal micropylar plate.