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The melanin content in the human body is high, so the color is black and yellow, and vice versa.
In our basal lamina, an irregularly shaped, transparent cell can be seen between the basal cells, called Myla.
Ning melanocytes; It can produce melanin granules and send them to the basal cells, the spiny cells, so that these cells are.
Contains melanin granules. Therefore, the amount of melanin content in ** is manifested in different colors on **.
The amount of melanin depends on the strength of tyrosinase activity in melanocytes, and the stronger the tyrosinase activity, the more melanin is synthesized. The factors that can affect the activity of tyrosinase all have an impact on the formation of melanin, the most important of which is genetic factors.
The genetic factors of the same race are different, so the amount of pigment produced is also different, showing different skin tones.
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Some people are born dark because each person's genes determine the speed and condition of melanin secretion in their body, resulting in ** skin color.
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Born with ** black, it is mainly related to genetics. This is caused by the patient's high melanin secretion. Patients who are born with ** black can be made white by their own maintenance.
You can use a 3:1 mixture of white vinegar and glycerin, and apply it to the face to have a certain whitening effect. It can also be powdered with traditional Chinese medicine such as Baiji, Baizhi, Coix seed, Angelica dahurica, white silkworm, etc., to make ** face compress also has a certain whitening effect.
You can also apply a mixture of egg whites, honey, and milk to the face.
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Because people are born black The main reason is related to genetics, such as the probability of the baby born from the parents black will be large, if one of the parents has a black complexion, the baby may not be black with the other party, and it may be black.
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Genetically different, Africa is born black, Chinese marry it, eight generations are black. Genes can't be changed within eight generations.
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If some people are born with ** black, this is also a genetic problem, or they don't pay attention to maintenance on weekdays, love to bask in the sun, and so on.
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The color of the person is determined by genes, that is, the melanin content in the **, the melanin content is high, the color is black and yellow, it will be born black, and the melanin content is less, and the color will be fair. Asians are generally yellow**, of course, some people's **black is also related to the acquired ultraviolet radiation, too much exposure to ultraviolet rays will damage the **barrier, more likely to produce melanin.
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This is different from each person's genes, determined by genes, some are black, some are fair, some are easy to be white, some are easy to be black, and some are easy to be black, all of them are different.
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Why are some people born dark, and this is related to your genetic hormones? So well, this is born with no way, sometimes for example, some people are born very white, it's the same reason.
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This is with the parents, some people are born black, and it is certain that his parents also have a black one, which is the cause of genes.
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It's that it's born black, which can't be changed, and it's beautiful.
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One is genetic, there is a lot of melanin in the human body, so it is black.
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If exposed to ultraviolet rays from the sun for a long time, the melanocytes in it tend to function more and produce more melanin, so that they will be tanned. It may also produce a lot of pigmentation, which will further darken the **.
If certain dermatitis, eczema, allergic diseases appear, then after the subside of inflammation, pigmentation is often left locally. This is a post-inflammatory pigmentation patch that can also lead to darkening. As the inflammation subsides, the pigmented spots are likely to fade gradually.
In addition, due to some internal diseases, as well as aging, it may also lead to poor nutritional status, lipofuscin precipitation of aging cells, which can also lead to darkening.
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It's inherently uneasy. Only pay attention to sun protection, in fact, there is no need to envy others, as long as you are healthy, it is the most beautiful.
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When irradiated by heat or sunlight**, melanocytes located within the basal lamina are excited and activated, and they are present in a 10:1 ratio within the basal cells, which have a dendritic shape and shuttle through the epidermal cells. Melanocytes contain pigment granules, which synthesize melanosomes in the crude endoplasmic reticulum, which catalyzes a series of tyrosine reactions and generates melanin proteins, while tyrosinase will be inactive and act as a transporter to transfer them to keratinocytes.
The more melanin is transferred to keratinocytes, the darker the skin tone. After people of the same skin color are also exposed to the same amount of sunlight, why are some people tanned and some people's ** has not changed much? This has to do with a number of factors.
It mainly depends on how much melanin is produced and how much melanin is transferred to keratinocytes, that is, the more melanin is produced and the more it is transferred to keratinocytes, the darker the skin tone, and vice versa.
Fact 2: The principle of tanning.
I believe that many Asian women are very concerned about skin whitening. There are many whitening products on the market, but how many people really know or understand how melanin is formed? Why do some people tan easily and others don't?
Before you buy whitening products, let's talk about the principle of tanning and understand the truth of the facts.
How is melanin formed?
When irradiated by thermal radiation or sunlight**, it excites and activates the stratum located in the basal layer
basale), melanocytes (present in a 10:1 ratio within basal cells), which have the shape of tree branches and shuttle through epidermal cells.
Melanosomes are synthesized in the crude endoplasmic reticulum, and tyrosinase, which is located in the Golgi apparatus, will catalyze a series of reactions in the melanocyte and generate melanin protein, while tyrosinase will be inactive and act as a transport to transfer it to keratinocytes. Therefore, the more melanin is transferred to keratinocytes, the darker the skin tone.
People who are afraid of black do not like melanin, however, melanin has its benefits, it has the effect of protecting the body against ultraviolet rays.
When the body is exposed to ultraviolet light, the melanocyte activating enzyme (tyrosinase) accelerates the catalytic action to produce melanin.
For example, two people with different skin tones, after being exposed to the same amount of sunlight for the same time, those with lighter skin tones are prone to redness, for example, we often see foreigners sunbathing, getting red but not tanning. In addition, people with light skin tones are also prone to burns, while people with darker skin tones are less likely to burn.
It can be seen that melanin can block the damage of ultraviolet rays within a certain limit. That is, ** will be red or even black after being exposed to sunlight, which is caused by the accumulation of melanin in the superficial layer of the epidermis.
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"Darkening is sometimes a physiological phenomenon, sometimes a disease. For example, people who are often outside will be obviously blackened in summer due to sun exposure, especially the sun-exposed parts such as the face and neck, forearms, etc., which have obvious boundaries with the parts covered by clothes, but this kind of ** tanning will turn white by itself in winter. Some people have visible dark spots on their cheeks, sometimes associated with the use of hormones, or heavy metals such as lead or mercury.
Female facial dark spots are generally not a big problem, but if men have dark faces, especially obvious dark spots, they need to go to the hospital to check liver and kidney function. In addition, if the neck and armpits are black, it cannot be ruled out that it is acanthosis nigricans. It is common for the elderly to become dark in a short period of time, and a comprehensive physical examination is required. ”
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People who are afraid of black don't like melanin, but melanin has its benefits. When the body is exposed to ultraviolet rays, the melanocyte activating enzyme (tyrosinase) accelerates the catalytic action to produce melanin, which has the effect of protecting the body against ultraviolet rays. Therefore, people with lighter skin are more likely to be burned than those with darker skin after being exposed to the same amount of sunlight.
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The color is determined by the amount of melanin in it. In the alpine Nordic (cold zone), people will not be exposed to the scorching sun, and the body has very little melanin, so the skin color is mostly white; Due to the tropical areas where the sun is concentrated at the equator, it is often exposed to strong sunlight (ultraviolet rays), and the body is adjusted to produce a large amount of melanin, so that it is protected **, which is black or brownish-black; Temperate zones are neutral yellow or brownish yellow – (melanin).
Details:
In anthropology, skin color is considered to be a sign of an important relationship with racial differences. Compared to animals, human skin color varies from white to black. The factors that determine skin color are:
** The color and thickness of itself. The number and distribution of melanin granules, the number of pigments such as carotene, and blood. The formation of differences in the skin color of people is determined by melanin granules.
For example, the large number of melanin particles can block ultraviolet rays that are harmful to the wavelength of living cells, and can also block the wavelength of ultraviolet rays required to produce vitamin D. Therefore, in areas with strong sunlight, dark colors** are good for the body, while in areas with weak sunlight, light colors** are good for the body.
Ethnicity is affected by skin color:
With regard to racial divisions, the prevailing view is that there are three main categories: Caucasian, East Asian, and Negro-Australian.
The genetic characteristics of skin color are one of the indicators of racial classification, but there are still large differences in skin color within the three major human races. For example, the Caucasian race includes Europeans, Arabs, and Iranians, among which Europeans have the lightest skin tone; East Asian races include people from Central, East and Southeast Asian countries, and Southeast Asian residents have significantly darker skin tones. Negro-Australians are also often divided into black and brown races, with the Negro race being relatively light-skinned in North Africa and darker in southern Africa.
Probably that's the rule.
Indians are more difficult to classify. The earliest inhabitants of the area should be said to be of the East Asian race, but the Aryans of the ancient Caucasian race invaded there thousands of years ago, and later the people of Iran and Central Asia invaded there in large numbers, so it is difficult to say whether the Indians belong to East Asia or the Caucasian. With regard to skin color and ethnicity, it is important to note that the impact of historical migration and interracial movement has been enormous.
For example, the Finns in Europe, from the linguistic characteristics, their ancestors came from the East Asian race in Asia, but the current Finns basically reflect the physical characteristics of the Caucasians.
In the past, Western scholars used a discriminatory perspective to distinguish races, and regarded brown and black races as inferior people, and after coming to China, in order to protect their superior status, they regarded the tanned skin color of farmers as the standard skin color of East Asia, and called yellow people, but there was little difference in Eurasian skin color genetically.
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