Answer:
The heart has four chambers — two upper chambers (called atria) and two lower chambers (ventricles). The heart has valves that temporarily close to permit blood flow in only one direction. The valves are located between the atria and ventricles, and between the ventricles and the major arteries from the heart.
Normal heart sounds are called S1 and S2. They are the “lubb-dupp” sounds that are thought of as the heartbeat. These sounds are produced when the heart valves close.
Because the heart is also divided into a right side and a left side, sometimes these sounds may be somewhat divided — most commonly noted is a split S2, caused when the right and left ventricles contract at very slightly different times. This is normal, but occasionally the nature of the split can indicate an abnormality such as enlargement of one of the ventricles.
Murmurs are blowing, whooshing, or rasping sounds. They are the result of vibrations caused by turbulent blood flow patterns. This can happen when a valve does not close tightly (such as with mitral regurgitation), or when the blood is flowing through a narrowed opening or a stiff valve (such as with aortic stenosis).
Step-by-step explanation: