Hair is a protein filament that grows from follicles in the skin. Hair is one of the defining characteristics of mammals.
There are three main types of hair:
– Vellus hair is short, fine, and lightly pigmented. It is most common on women and children.
– Terminal hair is long, thick, and darkly pigmented. It is common on men and in areas where the skin is thick, such as the scalp, beard, and chest.
– Lanugo hair is very fine, short, and light-colored. It is found on fetuses and newborns.
Hair growth is cyclical. The growth stage (anagen) is followed by a transitional stage (catagen), which is followed by a resting stage (telogen). At any given time, most of the hair on the head is in the anagen stage, while the rest of the hair is in the telogen stage.
Hair growth is controlled by hormones. The main hormone that controls hair growth is testosterone. Testosterone is produced by the testes in men and the ovaries in women.
Hair is composed of keratin, a protein that is also found in nails and the outer layer of skin. The hair follicle is the structure that anchors the hair in the skin. The follicle consists of a sebaceous gland, which produces sebum, and a dermal papilla, which contains capillaries and nerve endings. The hair shaft is the visible part of the hair. The hair shaft is composed of three layers: the cuticle, the cortex, and the medulla.
The cuticle is the outer layer of the hair shaft. It is made up of overlapping scales that protect the cortex and the medulla.
The cortex is the middle layer of the hair shaft. It is made up of long, twisted protein fibers.
The medulla is the inner layer of the hair shaft. It is made up of air-filled cells.
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How does hair become hair?
Hair is a protein filament that grows from follicles in the skin. The average human head has about 100,000 hairs. Each hair grows from a follicle in the skin. The hair on the head grows about 0.3 to 0.5 inches (0.8 to 1.3 cm) per month.
The hair on the head is divided into two parts: the root and the shaft. The root is the part of the hair that is embedded in the skin. The shaft is the part of the hair that sticks out of the skin.
The root of the hair is attached to a bundle of nerves and blood vessels called the hair follicle. The hair follicle is located in the dermis, the layer of skin that lies below the epidermis.
The dermis is made up of two parts: the papillary layer and the reticular layer. The papillary layer is the thin layer of skin that lies just above the dermis. The reticular layer is the thick layer of skin that lies below the papillary layer.
The hair follicle is located in the papillary layer of the dermis. The hair follicle is surrounded by a layer of connective tissue called the areolar connective tissue. The areolar connective tissue contains the blood vessels and nerves that supply the hair follicle with nutrients.
The hair follicle is a sac-like structure that contains the root of the hair, the sebaceous gland, and the arrector pili muscle. The sebaceous gland is a small gland that produces sebum, a type of oil that helps to lubricate the hair and the skin. The arrector pili muscle is a small muscle that contracts to make the hair stand up.
The hair follicle is attached to the skin by a structure called the hair matrix. The hair matrix is a mass of cells that lies at the base of the hair follicle. The hair matrix contains the cells that produce the hair shaft.
The hair shaft is made up of three parts: the cuticle, the cortex, and the medulla. The cuticle is the outermost layer of the hair shaft. The cortex is the middle layer of the hair shaft. The medulla is the innermost layer of the hair shaft.
The cuticle is made up of thin, overlapping scales that protect the cortex of the hair shaft. The cortex is the thickest part of the hair shaft and contains the cells that give the hair its color and strength. The medulla is a thin layer of cells that run the length of the hair shaft. The medulla is not always present in human hair.
The hair follicle is a dynamic structure that constantly renews itself. The cells in the hair matrix at the base of the hair follicle constantly divide and produce new cells that become the hair shaft. The old hair shaft is pushed out of the hair follicle and replaced by a new hair shaft.
Where does hair formation start?
Where does hair formation start?
This is a question that has long been debated by scientists. The answer is not yet fully understood, but there are several theories on the matter.
One theory suggests that hair follicles originate in the embryo in the region of the spinal cord called the neural crest. From here, they migrate to the skin, where they form the hair follicles.
Another theory suggests that hair follicles originate in the skin itself. This theory is based on the observation that some skin cells can form hair-like structures when grown in a lab dish. It is possible that these skin cells give rise to the hair follicles.
The answer to this question is still being studied, and scientists are working to determine which of these theories is correct.
How many hairs regrow a day?
How many hairs regrow a day?
It is difficult to give a precise number as different people will experience different rates of hair regrowth. However, on average, it is thought that around 100-150 hairs will regrow each day.
There are many factors that can influence hair regrowth, including age, genetics, and overall health. The rate of hair regrowth can also vary depending on the area of the body. For example, the hair on the head typically grows more quickly than the hair on the face or other parts of the body.
There are a number of things that can be done to encourage healthy hair growth. Eating a balanced diet, getting enough exercise, and avoiding stress are all important. using a good quality shampoo and conditioner can also help to promote healthy hair growth.
Is hair dead or alive?
Your hair is not alive. Hair is a product of the skin’s sebaceous glands and it is composed of a protein called keratin. Dead skin cells and sebum, which is an oily secretion from the sebaceous glands, make up hair.
Does hair grow back if it falls out from the root?
Does hair grow back if it falls out from the root?
There is no definitive answer to this question since hair growth and regrowth can be affected by a variety of factors, including genetics, age, health, and lifestyle choices. However, in most cases, hair does grow back if it falls out from the root.
The root of a hair is located at the base of the shaft, and it is from the root that hair growth begins. The root is also where the hair follicle is located, and it is the follicle that produces hair.
Hair growth occurs in cycles, and each hair follicle goes through three main stages: the anagen phase, the catagen phase, and the telogen phase. The anagen phase is the growth phase, and it is during this phase that the hair follicle produces new hair. The catagen phase is the transitional phase, and it is during this phase that the hair follicle begins to shrink. The telogen phase is the resting phase, and it is during this phase that the hair follicle is dormant.
Typically, hair will stay in the anagen phase for two to six years, the catagen phase for two to three weeks, and the telogen phase for two to four months. At any given time, about 85-90% of the hair on the head is in the anagen phase, 2-3% is in the catagen phase, and the remaining 6-10% is in the telogen phase.
When a hair falls out, it is usually because it is in the telogen phase and has reached the end of its life cycle. However, hair can also fall out from the root if it is pulled out or if it is cut off close to the root. In most cases, hair will grow back if it is pulled out or cut off close to the root, but it may take a few months for the hair to regrow fully.
While there is no guarantee that hair will grow back if it falls out from the root, in most cases it will. If you are concerned about hair loss or hair regrowth, it is best to consult with a doctor or hair restoration specialist to determine what might be causing your hair loss and what can be done to promote hair regrowth.
What is the secret of hair growth?
What is the secret of hair growth?
There is no one definitive answer to this question. However, there are a few things that are known to promote healthy hair growth.
One important factor is diet. Eating a balanced diet that includes plenty of protein, fruits, and vegetables is essential for healthy hair growth.
Another key factor is hydration. It is important to drink plenty of water each day to keep your hair healthy and hydrated.
Another important factor is stress. It is well known that stress can have a negative impact on hair health. Finding ways to manage stress can be helpful in promoting healthy hair growth.
Finally, regular haircare is also important. shampooing and conditioning your hair regularly helps to keep it healthy and hydrated.
Does hair change every 7 years?
There’s a lot of debate over whether hair changes every seven years or not, and the answer is a little bit complicated. The bottom line is that the rate at which hair changes may vary from person to person, and it’s also dependent on the individual’s hair type.
Generally speaking, however, hair does go through changes every seven years or so. This is especially noticeable when people reach middle age, as their hair may start to thin out or recede. Additionally, gray hairs may start to appear as people get older.
While there’s no hard and fast rule when it comes to hair changes, most people will see some sort of transformation in their locks every seven years or so. If you’re curious about when your specific hair changes might take place, consult a hair stylist or dermatologist for more information.”