Openings of auricles into ventricles are guarded by valves.

Atrioventricular valves:

1. Valves are connective tissue flaps that are linked to the papillary muscles of the ventricles by multiple connective tissue cords.
2. They ensure unidirectional flow and prevent the backflow of blood.
3. The valves present between the auricles and ventricles are called atrioventricular valves/ cuspid valves.
4. These are of two types: Tricuspid and bicuspid (Mitral) valves.
5. Tricuspid valves are present between the right auricle and ventricle.
6. Bicuspid valves are present between the left auricle and ventricle.
7. When auricles contract, the cuspid valves open.