wear your heart on your sleeve. to make your feelings and opinions obvious to other people John's always worn his heart on his sleeve, so there's no doubt who he'll be supporting. See also: heart, on, sleeve, wear. Related vocabulary: wear something on your sleeve.
In many bivalves and snails, and in cephalopods, part of the mantle is modified into a siphon, which can be used to pump water through the mantle cavity for respiration, feeding and/or jet propulsion. Freshwater and marine mollusks have gills (called ctenidia) for respiration, located in the mantle cavity. In most bivalves, these are enlarged and serve to trap food particles as well (Morton 1983).
â¢ Respiration â Most mollusks respire with gills, which are located in the mantle cavity. The mantle cavity is a space between the mantle and the visceral mass. â Mollusk gills extract 50% or more of the dissolved oxygen from the water that passes over them.â Most terrestrial snails have no gills.dditions and changes to the original content are the responsibility of the instructor. Mollusks and Annelids continued â¢ Marine Worms â Marine segmented worms are members of the class Polychaeta, the largest group of annelids.