Anatomy of human body bones

Human Skin Function Pigmentation Skin Hair What is Skin

When we think about the human body, the heart, liver or brain we immediately classify among the organs, because they have their own specific functions.

But did you know that the skin is also an organ?

The Skin is the human body’s largest organ.

While other organs take up little space or area, the skin stretches over the entire surface of the body, creating one layer, with a total area of about two square meters.
The number of complex structures which are found in every square inch of skin is fabulous.

What is Human Skin Made of?

The skin consists of two layers of tissue.
One is thicker and deeper and is called fur.
Above it is the second layer - the epidermis.
The two layers are connected to the lower layer in the upper wave-drawn, with which is firmly connected.
Therefore, the skin and forms a wavy ornament that can be observed in some parts, for example at the hand fingers.

The top layer of skin, the epidermis, has no blood vessels, and quite on the surface consists of cells of various shapes placed in layers that are at the top hardened.
This is very good because the last one, the hard part, protects the body. It is not sensitive to pain, and even the water does not affect it.
In places where it is thickest (eg heel, blisters, etc.) it also provides higher resistance to electricity.
The deepest layers of epidermis are alive and their task is to generate new cells.
Stem cells suppress these new cells up, and they are separated from their source of food and eventually dye transforming into hard layer.
During the day, due to the many activities that are carried out, such a myriad of dead cells disappear, and immediately new ones are created that replace them.
That is why our skin remains young.
In the skin, there are about thirty layers of hardened cells.
Whenever a surface layer is wasted, due to washing or friction, a new layer is immediately ready to replace it.
As many layers go to waste, there are always so many new, deeper ones, replacing them.
Therefore, the skin can be washed and rubbed in order to maintain it clean, without inflicting any damage to it.

Skin pigmentation

People whose skin is whitest, live in the north of Europe. These are Nordic.
Those people with darkest skin, inhabit West Africa.
The population of South Asia is characterized by a tawny-skinned.
However, most of the inhabitants of the planet do not have a white or black or yellow skin, but countless shades between light and dark.

What causes the color of the skin, hair and eye color in humans?

The reasons lie in numerous chemical processes that take place in our body. In skin tissue, there are certain basics of color, called chromogens, which are actually colorless. When certain enzymes act on the basis of color, we get certain color.
Without the presence of substances that give color, skin is gray and whitish.
The color of human skin depends on three colored substances or dyes that are found in the human body.
The first of these substances is melanin, with brown color.
The other is carotene, a substance that has a yellow color.
The third is called hemoglobin and a red-colored substance found in the blood.
Skin color depends on the relation of these four colors: light grey, yellow, brown and red. All existing color are created by mixing these primary colors.

Skin hair - how skin hair grows?

As the main feature of birds are feathers, so the hair is a characteristic of mammals.
Why mammals have hair?
The main task of the hair is to keep the body heat.
In the tropics, however, it has contrary role. Some tropical animals are protected by their fur from direct sunlight.
Very long hair on some parts of the body usually has a special role.
For example, the mane can protect the animals neck from the teeth of its enemies, tail can serve as a defense against insects, “crest” on the head of the males attract females. Sharp spines, which are actually collected strands of hair, allow sea piglet to defend itself against the enemies.
Also, the hair can serve as an organ of touch. Cat whiskers have special nerves that respond quickly to touch.
We can see that the hair of different mammals may have a different role.
But what about the hair of people?
We know that beautiful hair can make a woman more attractive to men. But we must assume that the hair of people used to have more practical meaning than it has today.
When a child is born, it is covered with soft feathery hairs.
They soon are replaced with thin body hair and soft hair that we see in all children.
Then comes the age of puberty and child hairy blanket changes into the final hairy blanket as it is on grown human.
Development of the final hairy layer is regulated by the sex glands. Influenced by the work of the male genitals, we grow beards, mustaches and body hair, while hair growth slows or stops.
The effect of female sex glands is the opposite. Hair growth is increased, and the growth of the beard and body hair stops. This is why women do not have a beard.
These differences in the growth of hair in men and women we call "secondary sexual characteristics”.
These are the second consecutive features that distinguish the two sexes.