where does the right atrium recieve blood from
Atrium (heart) Humans have a four-chambered heart consisting of the right atrium, left atrium, right ventricle, and left ventricle. The atria are the two upper chambers. The right atrium receives and holds deoxygenated blood from the superior vena cava, inferior vena cava, anterior cardiac veins and smallest cardiac veins and the coronary sinus, which it then sends down to the right ventricle (through the tricuspid valve) which in turn sends it to the pulmonary artery for pulmonary circulation. The left atrium receives the oxygenated blood from the left and right pulmonary veins, which it pumps to the left ventricle (through the mitral valve) for pumping out through the aorta for systemic circulation.[2][3]
Heart The heart has four chambers, two upper atria, the receiving chambers, and two lower ventricles, the discharging chambers. The atria open into the ventricles via the atrioventricular valves, present in the atrioventricular septum. This distinction is visible also on the surface of the heart as the coronary sulcus.[17] There is an ear-shaped structure in the upper right atrium called the right atrial appendage, or auricle, and another in the upper left atrium, the left atrial appendage.[18] The right atrium and the right ventricle together are sometimes referred to as the right heart. Similarly, the left atrium and the left ventricle together are sometimes referred to as the left heart.[6] The ventricles are separated from each other by the interventricular septum, visible on the surface of the heart as the anterior longitudinal sulcus and the posterior interventricular sulcus.[17]