The human scalp sheds 50–100 hairs each day.

The human scalp sheds 50–100 hairs each day.
 So what keeps you from balding? Stem cells, of course. At the base of a hair follicle, a population of stem cells wraps around the follicle, creating a compartment, called the “bulge." Like intestinal stem cells, these bulge stem cells have high proliferative capacity and are multipotent. In transplants, these cells can regenerate not only lost hair but also sebaceous glands and epidermis, too.

Image: Here, individual murine tail hair follicles are imaged. Stem cells are labeled green, and all cells are stained red with membrane dye.