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

/oper·cu·lum/ (o-per´ku-lum) pl. oper´cula   [L.]
1. a lid or covering.
2. the folds of pallium from the frontal, parietal, and temporal lobes of the cerebrum overlying the insula.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.

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.

operculum

[ōpur′kyoo͡ləm] pl. opercula, operculums
Etymology: L, lid
a lid or covering, such as the mucous plug that blocks the cervix of the gravid uterus or the temporal operculum of the cerebral temporal hemisphere that overlaps the insula as an extension of the superior surface of the temporal lobe. opercular, 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]

operculum

pl. opercula [L.]
1. a lid or covering.
2. the folds of pallium from the frontal, parietal and temporal lobes of the cerebrum overlying the insula.
3. gill cover in a fish.

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.
References in periodicals archive ?
Type oS eyes are single simple ocelli scattered on the brim of the operculum and are found in some Pomatostegus (Fig.
As with the findings of Koike (1978) in Haliotis tuberculata, cephalic tentacles, foot, and operculum appearance were noticed in posttorsional veligers in H.
Central Arteries (CA): The artery extends out and exits from the central portion of the operculum then passing inside the central sulcus.
Opening the operculum of its hermit kingdom, the snail comes out of its shell.
Melanotaenia laticlavia is also distinguished by the dark upper and lower caudal-fin margins (also shared by M irianjaya), the possession of a dark submarginal stripe and prominent white outer margin on both dorsal and anal fins (only on the dorsal fin of other Ayamaru complex species), broad blue grey zone on lower side (tapering porteriorly), and a red spot on the operculum, which although common in the genus, is either rudimentary or absent on other Ayamaru complex species.
Different body parts of fish such as; head, eyes, operculum, gills, buccal cavity, skin and all fins were examined for fungal infection.
The first step of our project was to test predation effectiveness of Belostoma lutarium on both types of freshwater snails, lunged snails (Sub-class PULMONATA) without an operculum, and gilled snails (Sub-class PROSOBRANCHIA) with a hard protective operculum cover.
By contrast, females on average had higher density in the left frontal pole, and larger volumes in the right frontal pole, inferior and middle frontal gyri, pars triangularis, planum temporale/parietal operculum, anterior cingulate gyrus, insular cortex, and Heschl's gyrus; bilateral thalami and precuneus; the left parahippocampal gyrus, and lateral occipital cortex.
spindale but meat like pieces of all the 18 goats were positive for large no of long spindle shaped ova with terminal spine and lacking of operculum.
The quantity of gibberellin that is necessary to promote germination depends on the degree of restriction of embryo elongation imposed by the endosperm and tegument (DEBEAUJON; KOORNNEEF, 2000); the removal of either the operculum or opercular tegument is efficient in promoting germination in numerous palm species (CARPENTER et al.
Later, fish lost balance, became exhausted, lost consciousness owing to respiratory incumbency and finally settled down passively at the bottom of the tank with the operculum wide open and ultimately died.