Why can human hair grow indefinitely?

Because 85% of human hair is in the anagen phase, 1% is in the catagen phase, the hair in the catagic phase no longer grows, the hair follicles begin to shrink, and the hair follicles in the telogen phase account for 14%, the hair follicles completely shrink, because the vast majority of the hair is in the anagen phase, and the hair in the telogen phase will enter the next growth phase after falling off, so the hair can grow endlessly.

Hair, in medicine, hair is also nutritious, human beings are absorbing nutrients every day, releasing carbon dioxide, and the roots of hair are also crazy according to the nutrients that people absorb.

Hair, something peculiar to humans.

I don't know if you've noticed, but chimpanzees, although they are close relatives of humans, don't need to get a haircut for the rest of their lives, because their hair doesn't grow consistently at all. This is also the case with many hairy animals in nature, as their hair does not continue to grow after it has grown to an appropriate length to maintain body temperature.

Most of the animal's body is covered with hair, but in the process of evolution, we humans have gradually lost the thick hair on our bodies. A new study by researchers at Washington University School of Medicine in St. Louis has found that human hair is not the same thing as animal hair, because it doesn't grow when it reaches a certain length, while our hair can grow forever. This is the real reason why people need haircuts and chimpanzees don't need haircuts.

There will be this phenomenon.

The maximum time is 1, though

months or 2 months stop long. It doesn't grow for a year or two, and it's generally a person who gets his hair often, and his hair doesn't grow if he gets hurt all the time. You stop for a while, don't get your hair down, don't wear a hat, let your hair pass through the air, and keep your own mental effect.

Being a little lighter is also good for your hair.

Why does human hair grow indefinitely and keep getting longer? What does it do?

Hehe! Eat and pull!

I have to eat it if I pull it!

Trouble not?

Hello lz.

It is impossible to come.

The long cycle of the human cephalic source is about 2-5 years. At this age, hair tends to stop growing and fall out (the hair grows longer before it falls out, so the hair grows longer before it falls out).

So it doesn't grow infinitely under natural conditions! It's just that it grows at a noticeable rate and is extremely numerous, while in comparison, the growth cycle of most biological hairs is much shorter than ours (most of them are 1 year). Hence the illusion that our hair grows infinitely.

As for why our hair growth cycle is shorter than in other organisms, that's another question. This is because we humans have long stopped relying on hair to keep out the cold, and natural organisms also need to rely on hair to keep warm and moisturize. As a result, most biological hairs in nature follow a one-year cycle.

If the hair growth cycle is wrong due to mutation, it will be eliminated immediately; This is not the case with people, so our hair has degenerated a lot, and the hair retains a variation of a longer growth cycle (which is easier to care for and more popular with women in mate selection), which has been left to this day by natural selection.

Why does human hair grow continuously?

Not much is known about this issue at the moment.

Genetic mutations may be the main cause.

As for how to control hair growth, there are still many uncertainties, and scientists have yet to unravel some mysteries.

But hair growth can be linked to a myriad of genes.

And, even a change in just one gene can have a huge impact on hair growth.

Other hair-bearing animals use hair removal to metabolize their hair.

Haha,Then you don't know if you try to make plants or animals in your life.。。 Hahaha, actually, people eat too many hormones. I guess.

The amount of keratin in human hair is slightly different, keratin is a fibrous protein that forms the chemical basis of hair, fingernails, rhinoceros horn, and many external features of animals, the amount of keratin in human hair is not the same as the amount of keratin in the hair of chimpanzees and gorillas, although chimpanzees and gorillas are the closest to us humans in biological relationship, but they are still different in keratin content.

One possible reason for this difference is that people have human DNA called "pseudogenes" and are called hhaa

The real gene produces the keratin found in chimpanzees and gorillas, and although the same DNA sequence is also preserved in humans, human cells do not use this DNA to produce proteins, which is why scientists call this gene in humans a "pseudogene".

Neufeld and Conroy already had some ideas on how to distinguish the difference between hair and body hair, and they said that this would be difficult because there were no animal prototypes to experiment with, but they believed that such research could be carried out, for example, by taking a hair follicle from a human head and a hair follicle from a leg, and doing a genetic slice test to study the differences in the genes that control the activity of these hair follicles. Studying the differences between human hair follicles and chimpanzee hair follicles can also provide some clues. However, even if it were possible to identify the difference between hair and body hair, scientists may never be able to figure out why the hair evolved by humans was so different from the hair of the closest animal species, but at least Newfield and Conroy have raised the question.

That's supposed to be hair.

Why do humans grow hair... This is the time to investigate before the apes.

At that time, humans had no hair.

The sun is shining and the sun is soaking**, I can't stand it.

So the hair grew.

It's true. I don't tell him about ordinary people.

Although the function of hair in the human body is not as important as that of the heart, kidneys and other vital organs, it also plays an indispensable role: protecting the scalp, reducing and avoiding external mechanical (such as falling, bumping, smashing, beating, etc.) and chemical (such as acid, alkali, etc.) damage; cushion damage to the head; Prevent or alleviate the damage of ultraviolet rays to the scalp and tissues and organs within the scalp; It has a moisturizing and antifreeze effect on the head; Excretion, harmful heavy metal elements such as mercury and non-metallic elements such as arsenic in the human body can be excreted from the hair to the body; Metabolic action, providing an outlet for the secretion of sebaceous glands and sweat glands, as well as keeping warm in winter and dissipating heat in summer.

The scalp has a special place in **. It protects the skull and the brain within the skull. The scalp also provides a foothold for the hair.

Hair, in turn, plays a role in protecting the scalp and skull. The protection of scalp hair is more complex and involves more matters than the protection of other parts. Shampooing, combing, haircutting, perming, and dyeing hair are all important.

The selection and use of hair oils, sebums and shampoos, as well as hair protection and scalp massage, are also closely related to scalp and hair protection.