- Superior venacava: It brings deoxygenated blood from the anterior parts of the body and opens into the right auricle at the anterior end.
- Inferior venacava: It brings deoxygenated blood from posterior parts of the body and opens into the right auricle.
- Pulmonary veins: They bring oxygenated blood from lungs and open into the left auricle.
- Pulmonary artery: It arises from the right ventricle. It takes deoxygenated blood to the lungs for purification.
- Aorta: It is the largest blood vessel and arises from the left ventricle. It takes oxygenated blood from the heart to all the parts of the body. The openings of pulmonary artery and the aorta are guarded by semilunar valves.
- Coronary artery and coronary sinus: The coronary artery supplies oxygenated blood to the wall of the heart and the coronary sinus or coronary vein receives the blood from the wall of the heart.