They are very interesting questions!
Each strand of hair on your head originates from its own tiny seed in your skin called a follicle. Within these follicles, cells divide and form a protein called keratin, which is what the hair is made off. Interestingly, fingernails, toenails, and parts of our outer skin are also formed by keratin! The cells of keratin are considered to be living while it is inside the follicle, but are considered to be dead once the hair pushes out of the scalp and becomes a hair shaft. This is why it doesn't hurt when you get a haircut! Each follicle also has tiny blood vessels providing the oxygen and nutrients which continues the formation and growth of the hair shaft. The cells in the follicle continue to multiply and push out of the scalp. As more oxygen and nutrients go into the follicle, more hair forms and the hair grows longer!
This article was produced by Alyssa Bolter, Physician Assistant Student, and Chirag Lodhia, PTW Director