Difference between an atrium and ventricle of the heart

The heart has the upper part and the lower part. The upper parts are called the atria and the lower parts are the ventricles. The parts are called the chambers. The upper part(chamber) located in the right is called the right atrium. The upper part(chamber) in the left is the left atrium. The lower part(chamber in the right is called the right ventricle. The lower part(chamber) in the left is called the left ventricle. The atria receives blood from the body and from the lungs while the ventricles receives blood from the atria.