Also, Doppler can detect abnormal blood flow within the heart, which can indicate a problem with one or more of the heart's four valves. Color Doppler. Color Doppler is an enhanced form of Doppler echocardiography. With color Doppler, different colors are used to designate the direction of blood flow.
Quick Answer. The age at which people grow armpit hair varies, but for boys it is often between the ages of nine and 14. Girls typically begin to grow this hair between eight and 13 years of age. Keep Learning.
There are lots of them, including your body growing bigger, your voice changing, and hair sprouting everywhere. Most boys begin puberty between the ages of 9 and 14. But keep in mind that puberty starts when a boy's body is ready, and everyone grows at his own pace.