Operculum (fish) Operculum (fish) The operculum is a series of bones found in bony fish that serves as a facial support structure and a protective covering for the gills; it is also used for respiration and feeding. The opercular series contains four bone segments known as the preoperculum, suboperculum, interoperculum and operculum. The preoperculum is a crescent-shaped structure that has a series of ridges directed posterodorsally to the organisms canal pores. The preoperculum can be located through an exposed condyle that is present immediately under its ventral margin; it also borders the operculum, suboperculum, and interoperculum posteriorly. The suboperculum is rectangular in
Operculum (brain) frontoparietal operculum, covers the upper part of the insular lobe from the front to the back. The opercula lie on the precentral and postcentral gyri (on either side of the central sulcus). The part of the parietal operculum that forms the ceiling of the lateral sulcus functions as the secondary somatosensory cortex. Normally, the insular opercula begin to develop between the 20th and the 22nd weeks of pregnancy. At weeks 14 to 16 of fetal development, the insula begins to invaginate from the surface of the immature cerebrum of the brain, until at full term, the opercula completely cover the