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What Is An Hair?

Hair is simple in structure, but has important functions in social functioning. Hair is made of a tough protein called keratin. A hair follicle anchors each hair into the skin. The hair bulb forms the base of the hair follicle. In the hair bulb, living cells divide and grow to build the hair shaft.Hair is simple in structure, but has important functions in social functioning. Hair is made of a tough protein called keratin. A hair follicle anchors each hair into the skin. The hair bulb hair bulb The hair follicle is an organ found in mammalian skin. It resides in the dermal layer of the skin and is made up of 20 different cell types, each with distinct functions. The hair follicle regulates hair growth via a complex interaction between hormones, neuropeptides, and immune cells. https://en.wikipedia.org › wiki › Hair_follicle Hair follicle - Wikipedia forms the base of the hair follicle. In the hair bulb, living cells divide and grow to build the hair shaft.23 Jun 2021
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Hair is simple in structure, but has important functions in social functioning. Hair is made of a tough protein called keratin. A hair follicle anchors each hair into the skin. The hair bulb forms the base of the hair follicle. In the hair bulb, living cells divide and grow to build the hair shaft. Blood vessels nourish the cells in the hair bulb, and deliver hormones that modify hair growth and structure at different times of life.

Hair growth occurs in cycles consisting of three phases:

Anagen (growth phase): Most hair is growing at any given time. Each hair spends several years in this phase.

Catagen (transitional phase): Over a few weeks, hair growth slows and the hair follicle shrinks.

Telogen (resting phase): Over months, hair growth stops and the old hair detaches from the hair follicle. A new hair begins the growth phase, pushing the old hair out.

Hair grows at different rates in different people; the average rate is around one-half inch per month. Hair color is created by pigment cells producing melanin in the hair follicle. With aging, pigment cells die, and hair turns gray.

Hair Conditions

Alopecia areata

: Round patches of total hair loss, usually from the scalp. The cause of alopecia is unknown; the hair usually grows back.

Male pattern baldness

: The most common type of hair loss in men. Male pattern baldness usually includes either a receding hairline, hair loss at the crown, or both.

Female pattern baldness

: In women, hair loss usually includes uniform thinning across the scalp, with a preserved hairline. The crown may be affected, but hair loss rarely proceeds to baldness as in men. See a picture of female pattern baldness.

Dandruff

(seborrheic dermatitis): Ongoing mild inflammation of the scalp, resulting in scaly skin that may be itchy and flake off. Seborrheic dermatitis may also affect the ears and face.

Tinea capitis (

ringworm

): A fungal infection of the scalp, creating round patches of hair loss. Although the patches can appear in a ring shape, no worm is involved in tinea capitis.

Trichotillomania

: A mental disorder that includes the irresistible urge to pull out one's hair. The hair pulling results in patches of noticeable hair loss; its cause is unknown.

Head lice

: Tiny insects that live on the scalp and feed on blood. Preschool and elementary school-aged children and adults who live with children are most susceptible to catching head lice, which are only spread through close contact.

Telogen effluvium

: A month or two after a personal shock (such as surgery, childbirth, severe stress), hair can abruptly fall out in large patches. Typically, new hair starts regrowing right away.

Postpartum alopecia- hair loss after delivering a baby- is a form of telogen effluvium and usually resolves without treatment.

Folliculitis

: Inflammation of hair follicles, usually due to an infection.

Staphylococcus aureus

is a bacteria that frequently causes folliculitis. Acne is a form of folliculitis that is caused by inflammation. This inflammation can sometimes be worsened by the bacteria Propionibacterium acnes.

Piedra

(trichomycosis nodularis): Fungal infection of the hair shaft. Hard nodules made of fungus cling to hair fibers, sometimes causing hair loss.

Hirsutism

: A condition in which women develop male-pattern hair (such as facial hair). An excess of testosterone due to a medical condition is usually responsible.

Hair Tests

Hair DNA testing

: Hair follicles contain DNA; hair can be tested to establish paternity or as evidence in a crime investigation.

Hair drug testing: Many street drugs (or their breakdown products in the body) are absorbed into the hair. A sample of hair can be tested for recent drug use.

Hair analysis

: Testing of hair for toxic exposures, such as lead or mercury poisoning. These tests are limited by inconsistency and difficulty interpreting their results.

Hair Treatments

Minoxidil (

Rogaine

): A medicine applied to the scalp, which can help prevent hair loss in most people when used daily.

Finasteride

(Propecia): A medicine for men taken in pill form daily, which regrows some hair and prevents hair loss in most men who use it.

Hair transplants

: Surgery to remove skin and hair from the back of the scalp, and transplant groups of hair follicles to areas of thin hair.

Hair electrolysis

: A very fine needle is inserted into a hair follicle, and electrical current is applied. The electricity destroys the follicle, preventing hair growth.

Laser hair removal: A laser is aimed at the cells in the hair follicle, and the laser's high energy destroys cells there, preventing hair growth

12 Related questions Answers found

What is hair meant for?

Depending on where it is, hair has different jobs. The hair on your head keeps your head warm and provides a little cushioning for your skull. Eyelashes protect your eyes by decreasing the amount of light and dust that go into them, and eyebrows protect your eyes from sweat dripping down from your forehead.

What is black hair called?

Afro-textured hair, or kinky hair, is the hair texture of populations in Africa, their diaspora and parts of Southeast Asia.

What is human hair made of?

Hair is made of a tough protein called keratin. A hair follicle anchors each hair into the skin. The hair bulb forms the base of the hair follicle. In the hair bulb, living cells divide and grow to build the hair shaft.

How do hairs grow?

Hair grows from a root at the bottom of a follicle under your skin. The blood in your scalp goes to the follicle and supplies oxygen and nutrients to the hair root, which helps your hair grow. As your hair grows, it will push through your skin and pass by an oil gland.

What is the anatomy of hair?

Hair is a derivative of the epidermis and consists of two distinct parts: the follicle and the hair shaft. The follicle is the essential unit for the generation of hair. The hair shaft consists of a cortex and cuticle cells, and a medulla for some types of hairs.

What are the 4 types of hair?

There are four main types of hair texture: Type 1 - straight, Type 2 - wavy, Type 3 - curly and Type 4 - tightly curled. The hair type and texture can be further broken down into a, b and c based on the hair's curl pattern, density, porosity, width and length.

Where is hair formed?

Hair grows by forming new cells at the base of the root. These cells multiply to form a rod of tissue in the skin. The rods of cells move upward through the skin as new cells form beneath them. As they move up, they're cut off from their supply of nourishment and start to form a hard protein called keratin.

Why does hair exist?

While humans have developed clothing and other means of keeping warm, the hair found on the head serves primarily as a source of heat insulation and cooling (when sweat evaporates from soaked hair) as well as protection from ultra-violet radiation exposure. The function of hair in other locations is debated.

What is Type 3 hair?

Type 3 curly hair ranges from a light curl to tight, curly tendrils, and usually have a combination of textures. They are defined and springy, with more height and volume at the root than type 2s.

What is Type 2 hair?

Wavy hair, also known as type 2 hair, can be split into three different subtypes: 2A, 2B, and 2C. It is the hair type that sits in between straight and curly hair. Its pattern ranges from loose loops to 'S' shaped waves. What makes it different from the other hair types is the curls' shape.

What is Type 3 natural hair?

Type 3: Curly Hair Type 3 hair ranges from tight, curly tendrils to light curls. It generally has a combination of different textures. Type 3 hair types are also defined as springy curls. They have more volume as well as height at the roots than type 2 hair types, which are wavy. Type 3A: Your curls are big and loose.

Is my hair 3C or 4A?

The essential quality that separates one from the other is the size of the curls. 3C hair strands have larger curls than 4A hair, which are a bit more tightly coiled. 3C hair has a reputation for being tightly densely packed, but otherwise soft to touch.