Circulation in Frog

Closed circulatory system with a 3-chambered heart (2 atria, 1 ventricle); Accessory chambers: Sinus venosus (receives blood) & Conus arteriosus; RBCs are oval, biconvex, and nucleated; Possesses both Hepatic portal system (gut to liver) and Renal portal system (lower body to kidneys).