Millions of Americans Suffer From Hair Loss
May 06, 2013
John Ertel started the Internet website for hair loss, regrowth.com.
This is Science in the News, in VOA Special English. I’m Shirley Griffith.
And I’m June Simms. Today we talk about hair. We will tell what hair is, how it grows, and some of the main reasons people lose it.
Hair has always been an important sign of beauty. This is especially true for women. Next to the face, hair is one of the main qualities people look for when they consider a woman’s beauty. Whether long or short, curly or straight, hair often gets a lot of attention.
Each hair on a person’s head grows from a single tube-like hole in the skin called a follicle. People are born with all of the hair follicles they are ever going to have. The average person has about one hundred thousand hair follicles. They begin to form on a fetus around the third month of pregnancy.
The part of the hair under the skin is known as the hair root. The hair sticking out from the skin is known as the hair shaft. The shaft is made up of dead cells that have been pushed up through the root. At the base of the hair root is a small ball-like formation called a bulb. This is where new cells are formed. These cells receive nutrition from the blood supply under the skin.
As new cells form, the older cells are pushed up through the root. In time, the old cells are cut off from the blood supply and begin to form a hard protein called keratin. Keratin is the same protein found in our skin and nails. These dead cells and keratin are what make up the hair shaft. This whole process is what causes hair to grow.
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2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25