A pattern, apart from the term's use to mean template, is a discernible regularity in the world or in a manmade design. As such, the elements of a pattern repeat in a predictable manner. A geometric pattern is a kind of pattern formed of geometric shapes and typically repeated like a wallpaper.
The vena cava is the major vein that returns blood to the right atrium of the heart. The vena cava superior returns blood from the head, neck, upper extremities, and chest. The vena cava inferior returns blood from the lower extremities, the pelvis, and the abdomen.
The circulatory system is made up of the heart and blood vessels. The heart pumps oxygen-rich blood through vessels called arteries. Veins carry blood from various parts of the body back to the heart. Arteries and veins are connected by tiny capillaries (KAP'ih-laireez). The heart's right side receives dark bluish blood from the superior and inferior vena cava. (The superior vena cava is the large vein that brings blood back from the upper part of the body. The inferior vena cava is the vein that brings blood from the lower body.) The heart's right side pumps this blood to the lungs. There, waste gas (carbon dioxide) is removed and oxygen is picked up. The bright red oxygenated blood returns to the heart's left side.