Superior Vena Cava
Superior vena cava is also referred as precava. It is a large vein, but short in length, located above the heart. The venae cavae are the largest veins in the body. They carry deoxygenated blood to the right atrium of the heart. There is no valve between the superior vena cava and the right atrium of the heart. The blood flowing from the precava to the heart causes contraction of the heart. This vein is formed by the veins which return deoxygenated blood from the upper limbs, neck and head to the heart.
Inferior Vena Cava
Inferior vena cava is also known as the posterior vena cava. It is the second largest vein of the heart, located at the lower part of the heart. Inferior vena cava carries deoxygenated blood from the parts of the body lying in the abdominal region to the heart. The inferior vena cava also drains the deoxygenated blood into the right atrium. Two major leg veins, iliac veins form the inferior vena cava.
Aorta
Aorta is the largest and the main artery of the body that supplies oxygenated blood to the body system. It looks like a tube that is a foot long and about 1 inch wide. It starts from the left ventricle, over the heart, from where it divides into several arteries and supplies oxygenated blood to the entire body except the lungs. Aorta has four sections: ascending, arch, descending and abdominal aorta.
