1. The left auricle of the heart receives _______ blood from the lungs.   oxygenated   deoxygenated   2. When the auricles of the heart contract, the ventricles relax, and vice versa.   True   False   3. The process of circulation of blood in the heart begins with the _______ of the auricles of the heart.   relaxation   contraction   4. During the atrial systole, the openings of the pulmonary vein and the vena cava are _______.   open   closed   5. During the atrial systole, the atrial muscles _______.   relax   contract   6. With reference to the heartbeat, the word 'systole' refers to a relaxation phase whereas the word 'diastole' refers to a contraction phase.   True   False   7. During the ventricular systole, the semilunar valves are closed.   True   False