The World Around Us!

Chelonia, rhychocephalia and squamata has 3 chambered heart. Which is made up of only two atriums and a ventricle. their two loop system which is the Systemic loop which is from the heart to the body and back to the heart and the Pulmonary loop which is from the heart to the lungs back to the heart. 

On the other hand, Crocodilia has a 4 chambered heart which is made up of two atriums and two ventricles. They also usually have a partial septum but they can also have a full septum. A septum is what separates two chambers.