operculum
Quick Summary
The operculum, also known as the opercle, is a term used in invertebrate anatomy with a few distinct meanings. In many gastropod mollusks, it is a horny or shelly plate located on the posterior dorsal surface of the foot. This plate functions like a lid, closing the shell opening when the animal retracts inside. This is a crucial defense mechanism against predators. Some sea snails secrete proteins to form this operculum. The term operculum can also refer to the covering of a fish's gills. In some cases, opercular bones are the bony plates that support the gill cover in fish.1234
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seashell…use a calcareous or horny operculum (trapdoor) on the foot to seal off the aperture when the foot is withdrawn into the shell. In the cephalopods Nautilus and Spirula, the planospirally coiled shell consists of multiple chambers connected by a porous tube called the siphuncle. The chambers contain quantities of…
Read More…use a calcareous or horny operculum (trapdoor) on the foot to seal off the aperture when the foot is withdrawn into the shell. In the cephalopods Nautilus and Spirula, the planospirally coiled shell consists of multiple chambers connected by a porous tube called the siphuncle. The chambers contain quantities of…
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shell collecting…horny or calcareous door, or operculum. The careful collector makes it a point to preserve the door with the shell in his collection. After a mollusk has died other marine animals may become occasional inhabitants of the shells.
Read More…horny or calcareous door, or operculum. The careful collector makes it a point to preserve the door with the shell in his collection. After a mollusk has died other marine animals may become occasional inhabitants of the shells.
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