What term describes the noises produced by the beating heart?

• A. Heart Sounds
• B. Cardiac Output
• C. Pulse
• D. Blood Pressure

Answer: (A)

Heart sounds describe the audible noises the heart makes as it beats. These sounds come from the valves closing and the blood moving within the chambers during the cardiac cycle. The first sound, often described as "lub," happens when the atrioventricular valves close at the start of ventricular contraction. The second sound, "dub," occurs when the semilunar valves close at the end of contraction. Sometimes extra sounds (like S3 or S4) can appear in certain conditions, but the basic noises you listen for with a stethoscope are the two main heart sounds, which reflect valve function and the timing of the cardiac cycle.

This term is the right fit because it specifically refers to audible signals produced by the heart itself, unlike cardiac output (the amount of blood pumped per minute), pulse (the palpable arterial expansion felt on the skin), or blood pressure (the force of blood against vessel walls).