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
Rosie (given name) Rosie (given name) Rosie is a feminine given name of English origin. It is a diminutive form of the English language given name Rose, which is of Latin origin. Similar diminutives in other languages include: ' becoming ' in Spanish, and ' becoming ' in Slavic languages. Rosie is a nickname for variations of "Rose" such as "Rosalie", "Rosemary", "Roseanne", "Rosalyn", and others. Historically, Rosie has been a reasonably popular given name for infants in England and Wales during the early 21st century, as it was in Victorian times. It continues to be popular in Scotland, as well. However, it