Gdz Biologiia 7 Sumatokhin Klass Dvukhstvorchatye Molliuski Onlain Apr 2026

For further study and visual aids, students can refer to educational platforms like Yaklass or watch lesson summaries on YouTube .

: Students typically study the Anodonta (swan mussel), Unio (painter's mussel), and marine species like the edible mussel and giant clam. For further study and visual aids, students can

: Many species, such as scallops and oysters, are significant food sources for humans. Freshwater pearl mussels are also cultivated for pearl production. Freshwater pearl mussels are also cultivated for pearl

: They possess an open circulatory system with a heart and vessels. This shell consists of three layers: an outer

: The body is laterally compressed and enclosed in a bilateral shell. This shell consists of three layers: an outer organic layer (periostracum), a middle calcareous layer, and an inner pearly layer (nacre).

: They breathe through plate-like gills (ctenidia) located in the mantle cavity.