In the circulatory system of a frog, the single ventricle opens into a sac-like structure to pump blood out of the heart. Identify this structure and its anatomical position on the heart.

Step-by-step solution

In a frog's heart, the ventricle pumps blood out by opening into a sac-like structure called the conus arteriosus, which is located on the ventral side of the heart. The sinus venosus is a triangular structure that joins the right atrium to receive deoxygenated blood, not the structure the ventricle opens into. Answer: Conus arteriosus located on the ventral side