List the circulatory organs of the frog.

The frog’s circulatory organs are composed of the heart, blood vessels, and spleen. There are three chambers in a frog’s heart: two atria, which receive oxygenated blood from the lungs, and one ventricle, which pumps blood into the body. Veins and arteries are tubes that move blood to and from the heart, respectively. The frog spleen stores and processes old red blood cells and is located in the mesentery between the stomach and colon. The frog’s heart is located in the center of the body between the forepaws.