How the respiration of bivalves?

Bivalves, such as clams and mussels, respire using gills, which are specialized structures located within their shells. Water enters the mantle cavity through an inhalant siphon, passing over the gills where oxygen is extracted and carbon dioxide is released. The gills also play a role in feeding by trapping food particles. The oxygen-rich water is then expelled through an exhalant siphon.