In mathematics, mean has several different definitions depending on the context. In probability and statistics, mean and expected value are used synonymously to refer to one measure of the central tendency either of a probability distribution or of the random variable characterized by that distribution.
Red Blood Cell Route through the Cardiovascular System. Let us follow a single red blood cell (RBC) through one full cycle along the circulatory pathway Remember that RBCs carry oxygen throughout the body.Since the blood travels endlessly, an arbitrary choice must be made of a starting point to describe the RBC's route.. The RBC is then pumped through the pulmonary valve into the pulmonary artery and on to the lungs. There the RBC gives off carbon dioxide and picks up oxygen. 4. The RBC returns to the heart through a pulmonary vein, enters the left atrium, passes through the mitral valve, and flows into the left ventricle. 5.
The pulmonary circuit carries blood to the lungs to be oxygenated and then back to the heart. In the lungs, carbon dioxide is removed from the blood, and oxygen taken up by the haemoglobin in the red blood cells. The systemic circuit carries blood around the body to deliver the oxygen and returns de-oxygenated blood to the heart. Blood also carries nutrients and waste.