In the section pointing to the pulmonic valve which serves as the gateway from the right ventricle and the pulmonary circulation, the primary function is to prevent backflow of blood form the pulmonary trunk into the right ventricle. In the section pointing to the tricuspid valve, otherwise known as right atrioventricular (AV) valve, it functions to prevent backflow of blood from right ventricle to right atrium. In the section pointing to the aortic valve which serves as the gateway from the left ventricle and the pulmonary circulation, the primary function is to prevent backflow of blood from the aorta into the left ventricle. Lastly, in the section pointing to the mitral valve, otherwise known as the left atrioventricular (AV) valve, it functions to prevent backflow of blood from the left ventricle to the left atrium.