Atrium (heart) now used for an appendage of the atrium. Humans have a four-chambered heart consisting of the right atrium, left atrium, right ventricle, and left ventricle. The atria are the two upper chambers. The right atrium receives and holds deoxygenated blood from the superior vena cava, inferior vena cava, anterior cardiac veins and smallest cardiac veins and the coronary sinus, which it then sends down to the right ventricle (through the tricuspid valve) which in turn sends it to the pulmonary artery for pulmonary circulation. The left atrium receives the oxygenated blood from the left and right pulmonary veins, which it
Riley (given name) Riley (given name) Riley is a unisex given name, which first appeared as "Raghallach", which was originated on a man who died in the Battle of Clontarf. Its source gives its meaning as "valiant". Riley in the United States is mostly a girl's name. In 2017, it was the twenty-fifth most popular girl's name, and the 253rd most popular boy's name. The opposite is true for the UK, where it is primarily a boy's name, being the fortieth most popular name given to baby boys in 2016. Riley is also a popular surname. The surname's first variant is Ó Raghallaigh