Final answer:
The most common cause of blood flow turbulence is valve malfunctions. Heart murmurs, which are sounds produced by turbulent flow around damaged and insufficiently closed heart valves, can be detected with a stethoscope.
Step-by-step explanation:
The most common cause of blood flow turbulence is valve malfunctions. Turbulent flow occurs when the valves in the heart do not close properly, leading to backflow of blood and creating a turbulent flow. Heart murmurs, which are sounds produced by turbulent flow around damaged and insufficiently closed heart valves, can be detected with a stethoscope. Ultrasound can also be used to detect turbulence caused by valve malfunctions.