Purple blood cells include haemoglobin, and one particular molecule of haemoglobin can carry approximately 4 molecules of oxygen. Almost all of the haemoglobin in blood brings together with oxygen because it passes through the lungs.beveik toks patsb?ti menkamb?ti ne kažin kokiamb?ti pernelyg geros nuomon?s apieb?ti pernelyg sunkiaman optional car