Hair is much more complicated than it looks.
it’s possible for you to feel it at the root when it moves or gets pulled.
It protects your skin and traps particles like dust around your eyes and ears.
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it’s possible for you to express yourself through your hairstyle.
If your hair gets damaged, it can renew itself without scarring.
Hair covers almost every surface of the human body.
This article gives an overview of the structure of hair.
It explains how it grows, what its made of, and how it changes.
This is the largest number of hair follicles you will ever have.
Follicles do not continue to multiply during life.
Hair is made up of two separate structures.
Hair Follicle
The hair follicle is where your hair begins to grow and is held in place.
Its a stocking-like structure that starts in the epidermis, your skins top layer.
It extends to the dermis, your second layer of skin.
These nourish the hair root to keep it growing.
The follicle also contains the germinal matrix, where cells produce new hairs.
The follicle is lined by an inner and outer sheath that protects and molds the growing hair.
The inner sheath follows the hair and ends just before the opening of the oil gland, orsebaceous gland.
The outer sheath continues all the way up to the gland.
Thesebaceousgland producessebum, or oil, which is the bodys natural conditioner.
More sebum is produced during puberty, which is why acne is common during the teen years.
Sebum decreases with age, causing the skin to become dry.
Thearrector pilimuscle, a tiny bundle of muscle fiber, is attached to the outer sheath.
When the muscle contracts, it causes the hair to stand up, otherwise known as goosebumps.
Hair Shaft
The hair shaft is the part of the hair that we can see.
Once the hair grows beyond the skins surface, the cells arent alive anymore.
Its made up of three layers of keratin, a hardening protein.
It can have three layersthe medulla, the cortex, and the cuticle.
There are three stages of hair growth.
In the anagen phase, hair on the scalp grows for three to four years.
In the catagen phase, hair slows down its growth.
In the telogen phase, hair stops growing and stays in place until a new hair pushes it out.
This appearance is due to the shape of the hair.
Straight hair has a mostly circular circumference.
Strands of curly hair are flat.
The more circular the hair shaft, the straighter the hair.
The flatter the shaft, the curlier the hair.
The cross-sectional shape of hair also determines the amount of shine that the hair has.
Straighter hair is shinier because sebum from the sebaceous gland can easily travel down the hair.
As you getolder, your hair can changecolor, texture, and thickness.
Your hairs appearance is determined partly by the shape of your hair.
If your hair has a circular circumference, it will be straight.
If its more flat than round, it will be curly.
Summary
Your hair consists of a hair follicle and hair shaft.
The hair follicles in your skin contain living cells to allow your hair to grow.
The shaftthe part of the hair we seeis made up of dead cells and consists of three different layers.
you could help keep your hair healthy by taking care of your overall health.
Eating nutritious foods is one way to improve hair from the inside out.
Check with your doctor if you have questions onyour hairs growthand how it might be impacted by your health.
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