Observation is the active acquisition of information from a primary source. In living beings, observation employs the senses. In science, observation can also involve the recording of data via the use of instruments. The term may also refer to any data collected during the scientific activity.
About the Heart / Lung; Heart / Lung Center Data Profile; The aorta is the main artery that carries blood from the heart to all parts of the body except the lungs. The pulmonary artery is one of the two arteries that carry blood from the heart to the lungs. The vena cava is either of two large veins that return blood to the right atrium of the heart. The left atrium is the upper left chamber of the heart that receives blood from the pulmonary veins. The right atrium is the upper right chamber of the heart that receives blood from another part of the body and pumps it into a ventricle.
Valves of the Heart: Circulation of Blood, Part 1. The veins of the body all eventually drain into the right atrium, which is the receiving chamber of the right side of the heart. Once the right atrium is full, the tricuspid valve opens, allowing the de-saturated blood to flow into the right ventricle. The right ventricle then fills with the de-saturated blood.