operculum


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operculum

1. Zoology
a. the hard bony flap covering the gill slits in fishes
b. the bony plate in certain gastropods covering the opening of the shell when the body is withdrawn
2. Botany the covering of the spore-bearing capsule of a moss
3. Biology any other covering or lid in various organisms

Operculum

 

the fold of skin that covers the outside of the gill slits in the majority offish (except the shark and ray) and in the larvae of amphibians, especially tadpoles. The operculum of fish of the class Osteichthyes has bones. In the majority offish the operculum plays an active role in breathing: when it is lifted, a vacuum is created in the gill cavity, and water passes from the mouth and pharyngeal cavities into the gill cavity by way of the gill apparatus. It is possible to determine the age of some fish according to the annual rings on the operculum bones.

operculum

[ō′pər·kyə·ləm]
(anatomy)
The soft tissue partially covering the crown of an erupting tooth.
That part of the cerebrum which borders the lateral fissure.
(biology)
A lid, flap, or valve.
A lidlike body process.
References in periodicals archive ?
The complex might reflect the attachment site of an operculum, but muscle attachment just on the periphery of an operculum is not conducive to effective function.
We found that live snails that were exposed to different salinities showed some level of variation in climbing or sticking to the aquarium wall, secreting corporal mucus, closing the operculum, responding to a metal needle, and feeding and stooling responses (Table 1).
The foot is observed in a transverse section (i.e., perpendicular to the elongate shape of the foot), through the posterior region where it is adjacent but not attached to the operculum, such that the section produced circumferentially bears an epidermal surface.
Blanca con 1-2 bandas malva sin bandas palido Serie interna filiforme, Serie interna casi blanca, de hasta 3 mm de aplanada de apice largo irregular, verdosa, de hasta 7 mm de largo Operculum Verde palido Verde intenso con maculas purpura Estilos Purpura profundo de Verdes con maculas hasta 6 mm de largo purpuras de hasta 8 mm de largo Fruto Baya negra globosa a Baya negra ovoide-- subglobosa, parte oblonga, parte inferior inferior redondeada aguda mamilada Semillas Marron oscuro de hasta Negras de hasta 4.5 x 3 4.1 x 2.5 mm mm
FLOWERS DAY LENGTH January 12 1:20 pm February 21 12:42 pm March 20 11:50 am April 0 11:14 am May 0 10:48 am June 0 10:43 am July 0 10:44 am August 9 11:36 am September 9 12:15 am October 22 12:54 am November 33 1:22 pm December 26 1:29 pm Table 3--Measurements of floral parts MEARUREMENTS MEAN MODE STANDARD DEVIATION Diameter (cm) 7,9 7,5 0,724 Petal (cm) 3,3 3,2 0,277 Sepal (cm) 3,4 3,5 0,259 Bracts (cm) 2,6 -- 0,264 Peduncle (cm) 7,9 -- 1,322 Pedicel (cm) 1,8 1,9 0,244 Androgynophore (cm) 3,2 3,4 0,249 Ovary Diameter (mm) 3,7 1,6 0,539 Ovary Length (mm) 5,6 -- 0,396 Ant x Cor (cm)* 1,7 1,6 0,241 Ant x Ope (cm)** 2,9 2,9 0,316 ** Ant x Oper (cm) means the distance between the axis of anthers and the operculum, in centimeters.
A slit in the endocarp wall, where no pore or operculum is present, can provide another means of opening at germination.
parahaemolyticus are able to form biofilm a number of surfaces including glass, high-density polyethylene (HDPE), stainless steel, and operculum of M.
Feeding activity starts with rapid inhalation of water together with small food particles above the bottom through the mouth and rapid exhalation from beneath the operculum. Such activity continues constantly until they swim in a zigzag pattern to another place to feed or rest.
The analysis between FTD variants showed differences between bvFTD and nfvPPA into the left hemisphere to the connection between operculum with parietal and cuneus left with occipital superior gyrus (Figure 2(a)).
Inner margin of vasiform orifice smooth or dentate; lingula usually obscured; operculum covers 50% of the vasiform orifice.