Heart depending on what is counted as a chamber. The atrium and ventricle are sometimes considered "true chambers", while the others are considered "accessory chambers". Primitive fish have a four-chambered heart, but the chambers are arranged sequentially so that this primitive heart is quite unlike the four-chambered hearts of mammals and birds. The first chamber is the sinus venosus, which collects deoxygenated blood from the body through the hepatic and cardinal veins. From here, blood flows into the atrium and then to the powerful muscular ventricle where the main pumping action will take place. The fourth and final chamber is the
June (given name) dropped off the top 1000 list of names in 1987. In recent years, it has started to make a comeback: in 2017 it ranked 244th. As a boy's name, June reached a peak in 1922 at 697th, but then also declined and left the top 1000 list in 1939. June (given name) June is a female given name, but it is also used as a male given name in English-speaking countries. It comes from the name of the month, which is derived from Juno, the name of a Roman goddess. It is also a short form of the names Juniper,