: Some species (pearl oysters) produce pearls and mother-of-pearl (nacre) used in jewelry.
: They are filter feeders . Water enters through an inhalant siphon, passes over the gills where food particles are trapped, and exits through an exhalant siphon.
: Like most mollusks, they have an open circulatory system where the heart pumps blood into the body cavity. Internal Anatomy Summary Characteristic Digestive gdz biologiia 7 sumatokhin klass dvukhstvorchatye molliuski
Урок 2: Классы моллюсков - Ростелеком Лицей
: The body is laterally compressed and divided into two main parts: the trunk and the wedge-shaped foot . Unlike gastropods, bivalves lack a head, tentacles, and eyes. : Some species (pearl oysters) produce pearls and
: Species like oysters, mussels, and scallops are important food sources for humans and marine life.
: Swan mussels ( Anodonta ), thick-shelled river mussels ( Unio ), and giant clams ( Tridacna ). : Like most mollusks, they have an open
Mouth (near the foot), stomach, liver, and intestine. They lack a radula (grating tongue). Plate-like gills (ctenidia) located in the mantle cavity. Excretory Two kidneys that open into the mantle cavity. Nervous Simplified, consisting of three pairs of ganglia. Ecological and Economic Importance