Atrium (heart) of blood occurs. In birds, mammals, and some other reptiles (alligators in particular) the partitioning of both chambers is complete. Atrium (heart) The atrium is the upper chamber in which blood enters the heart. There are two atria in the human heart – the left atrium connected to the lungs, and the right atrium connected to the venous circulation. The atria receive blood, and when the heart muscle contracts they pump blood to the ventricles. All animals with a closed circulatory system have at least one atrium/auricle (humans have two atria). The atrium used to be called the "auricle", and
Sandra (given name) Sandra (given name) Sandra is a female name, which is often used as a short form for Alexandra or Cassandra. Alexandra is a feminine form of the male name Alexander, which is a romanization of the Greek name Ἀλέξανδρος "Alexandros". It is generally interpreted to mean "protector of man" or "defender of man". The name Cassandra is also from the Greek (: "she who entangles men"). Cassandra is known in Greek mythology, as the daughter of King Priam and Queen Hecuba of Troy. She was loved by Apollo and given the gift of prophecy but when she did not fall