Why Americans are blue eyes 20

The color of the eyes is determined by the pigment contained in the iris, which is blue in Europeans and black in Asians. Eye color is genetic.

Because they see the world in another color.

Scientists have found that the iris of our human eye is made up of five layers of tissue. They are the endothelial cell layer, the anterior bounding membrane, the stromal layer, the posterior bounding membrane, and the posterior epithelial layer. In these five layers of tissue, the stromal layer, the anterior bounding membrane, and the posterior epithelial layer contain many pigment cells, and the amount of pigment contained in these cells determines the color of the iris.

The more pigment contained in the pigment cells, the darker the iris and the darker the eyeballs. And the less pigment, the lighter the color of the iris, and the lighter the color of the eyeballs.

The pigment content in pigment cells is consistent with color and is related to ethnicity genetics. Orientals are people of color, and the iris has a lot of pigment, so the eyes look black; Westerners are white and have little pigment in the iris and blood vessels in the stromal layer, so the eyes look light blue.

First of all, the color of the eye actually refers to the color of the iris, and the color of the iris is determined by the amount of melanin. In addition to melanin, light is scattered to form blue, and blood is red, and these colors vary from one color to another, and when mixed, they form a variety of different eye colors.

There are only three primary colors of the human iris: brown, blue, and green. The other colors of the iris are variations of these three colors. People with albinism have a pink iris, which is due to the lack of pigment in the iris and only the color of the microvessels.

For example, dark brown, light brown and gray are all caused by the intensity of melanin, blue is the color produced by scattering, and red is the color produced by albino. When light brown is mixed with blue, it becomes green; Red and blue are mixed to create purple.

Eye color classification:

1.Brown brown is the most common human iris color. The brown iris contains a lot of melanin, and the dark brown iris looks like black. The brown iris is thought to be the dominant gene for the human iris, but recent research suggests that this is not necessarily true.

2.Hazel: The hazel eye is caused by a combination of Rayleigh scattering and moderate levels of melanin in the anterior membrane of the iris. Hazel is difficult to define. They are described as light brown or yellowish brown. Some people think that hazel is an intermediate color between brown and blue iris.

3.Amber and yellow amber are more common in other animals, it is lighter than brown and rarely occurs in humans, and is also known as cat's eye color. In Europe, the proportion is more prevalent, or more mixed-race.

4.The green-green iris is the rarest color. a higher proportion among the Celts, Germanic and Slavic peoples of Europe; Outside of Europe, some Pashtuns and Turks also have green iris. The ancient Kyrgyz too.

5.Gray is considered a variant of the blue iris. It is the second rarest color (after green).

6.Blue iris is more common in Europe, with about 8% of the world's population having a blue iris. More than 80% of Nordic people, such as Icelanders, Finns and Latvians, have blue eyes.

Foreigners' eyes are blue because the iris pigment content in foreigners' eyes is low, so the eye color is a lighter blue.

Eye color refers to the color of the middle part of the eyeball, which is covered with a layer of iris, which contains many pigment cells, and the amount of melanin in the pigment cells determines the color of the iris. The higher the pigment content, the darker the iris and the darker the eye color; The less pigment you have, the lighter the color of your iris and the lighter your eyes.

The iris is roughly divided into two layers: the front is the iris stroma and the epithelial cell layer that covers it; A layer of epithelial cells on the back of the iris, both of which contain pigments. The color of the iris is related to two pigments.

These two pigments are called melanin and lipopigment. Melanin is black and lipochrome is yellow.

Foreigner's eyes are astringentForeigner's eyes are blue, which is caused by genetics So they say that the living area is different from our Chinese living area They all have genetic reasons, and ** white eyes are blue This is the white race First, unique rabbit So what about our yellow race is black hair, black eyes This is a genetic reason.

Foreigners are born with blue eyes, and for no reason, it has something to do with their ethnicity.

It's a genetic problem of the human race!!

But not limited to "foreigners"!!

There are also such people among ethnic Russians and Uyghurs in China.

Of course, it also includes "former foreigners" who voluntarily become Chinese nationals and obtain Chinese nationality.

What are the blue eyes for Chinese people? What kind of people are there in the world? There are yellow people, white people, black people, and middle people, because white people, they evolved from ape-people, that is, blue eyes, so people are all blue-eyed.

Why are you blue-eyed? Foreigner, his foreign blood type is different from China, he is very white, not very black, they are blue doll in their eyes, and they are snow type to ask questions, so they are foreigners.

Foreigners ask foreigners why they have blue eyes? Because of the local climate and genetics, why do foreigners have blue eyes? It is related to the local climate and genetics.

Hello, foreigners' eyes are blue, and it is very likely that they are genetically responsible for their blue eyes.

That's because foreigners are of different races, living in a specific environment, and in order to adapt to nature, they become blue-eyed.

Because their genes don't code the same proteins as ours, so do the cells that control eye color.

People are of different races, and people in the world are divided into yellow people, white people

Individuals with blue eyes are their ethnicity issues.

Why do Chinese have black eyes?

The genes of the human body have been affected to varying degrees, and in the process of human evolution, due to the different living environments, the rise of people and the different cultures, so many different human races have been formed. The color of the eye is determined by the pigment contained in the iris, and the color of the eye is also determined by the corresponding amount and type of pigment. Therefore, the reason why foreigners' eyes are blue is actually because they have special genes that cause the variation of eye color.

According to scientists, most Asians and Africans have mostly brown and black eye colors, while white people are able to have blue and green background colors because of their special genes. Unlike Asians and Africans, Europeans and other Caucasian genes encode a special chromophobia that allows the human eye to reflect blue light from light.

Further analysis shows that blue eyes are not only determined by genes, but also related to a series of factors such as population migration, mixed-race marriage, and environment. However, these phenomena have not been extensively studied. At the same time, in the near future, with the development of science and technology, human understanding of genes will continue to deepen, which will also bring many unprecedented new perspectives and unique insights to this topic of general concern.

In conclusion, there is no obvious functional difference in eye color itself, and the emergence of different eye colors stems from long-term changes in genetics and human evolutionary history. However, people's preference and aesthetics of eye color also show that eye color represents the evolution of human aesthetics and cultural concepts to a certain extent, which also reflects our continuous exploration and understanding of the eye as an organ. <>

Americans have a wide variety of eye colors because the United States is a multi-ethnic and multi-racial country, and people's genetic backgrounds and genetic factors have led to a rich variety of eye colors. Here are some common eye colors for stuffy masks, including but not limited to Americans:

1.Dark brown: Dark brown eyes are common in Americans.

2.Hazel: Hazel eyes are also more common.

3.Blue: Blue eyes, although relatively rare, are still common among Americans.

4.Gray: Gray eyes are also present in some Americans.

5.Green: Green eyes are relatively rare, but some Americans have eyes of this color.

6.Silver: Silver eyes are also a very rare eye color that is rarely seen in Americans.

These colors are broadly categorized, and in fact there may be a variety of different subtle variations and mixtures of color in people's eye colors. In fact, there may be overlaps and differences between Americans' eye color and populations in other countries or regions, depending on genetics and demographics. <>

Americans have mostly blue eyes, some are brown, and a few are black. People have different eye colors, mainly due to the influence of genetics and pigmentation.

The color of the eye depends on the pigment content and structure in the iris. The iris is a colored ring of tissue located at the front of the eyeball that regulates the amount of light entering the eye by controlling the size of the pupil. In the iris there a pigment called melanin, which absorbs a portion of the light, and the unabsorbed light is reflected to form the color of the eye we see.

1.Genetic factors: Eye color is often the result of genetics.

Parents' genes determine their children's eye color. Most of the time, eye color is the result of polygenic inheritance and involves multiple loci. Certain genes affect the production and distribution of pigments, which determine the color of the eyes.

2.Pigment content: Eye color is mainly related to the amount of melanin in the iris.

People with higher melanin content tend to have dark eyes, such as brown or black; People with lower levels of melanin may have light-colored eyes, such as blue or gray. In addition, if the iris contains other pigments, such as yellow pigment or red pigment, it can also cause other colors of the eye.

3.Light scattering: In addition to the effect of macromelanin, the scattering of light in the eye segment can also affect the color of the eye. For example, people with blue eyes are usually because of structures in the iris that disperse and reflect light, giving us the blue we see.

It is important to note that eye color is a continuous spectrum and has many intermediate tones. The same parents may also have offspring with different colored eyes, due to genetic variation and the complexity of the gene combination. In short, <>