* Hair Follicle: The hair follicle is a small, pocket-like structure in the skin. At the base of the follicle is the hair bulb, which contains living cells.
* Cell Division: These living cells in the hair bulb divide and multiply. As new cells are produced, they push older cells upward.
* Keratinization: As the cells move upward, they become filled with a protein called keratin. This process, called keratinization, causes the cells to die.
* Hair Shaft: The dead, keratin-filled cells form the hair shaft, which is the part of the hair that we see.
* Growth Cycle: Hair growth follows a cycle with three phases:
* Anagen (Growth Phase): This is the active growth phase, which can last for years.
* Catagen (Transition Phase): This is a short transitional phase when growth slows down.
* Telogen (Resting Phase): This is a resting phase when the hair doesn't grow and eventually falls out. After the telogen phase, the follicle returns to the anagen phase, and a new hair starts to grow.
* Cutting vs. Growth: Cutting the hair doesn't affect the hair follicle or the growth cycle. The cells in the hair bulb continue to divide, keratinize, and push the hair shaft upward, even after it has been cut.
In summary, hair grows because of cell division in the hair follicle beneath the skin, and cutting the visible part of the hair shaft doesn't stop this process.