The skin under the microscope has a rather complex structure. In our article, we will consider the structural features of the integument of the body at the cellular level.
Why is skin an organ?
Our skin is not just a layer of the epithelium. It is formed by several types of tissue. You can verify this by examining the skin under a microscope. In the photo below, cells of various shapes and sizes are clearly distinguished.
Therefore, the skin is the organ - the largest in the human body. It can weigh up to 3 kg with an average thickness of 4 mm. The total skin area is 1.5-2 m squared. In different parts of the body, its thickness varies. It is the thickest and coarsest in places of greatest friction. For example, on the feet.
Human skin under a microscope
The skin consists of three layers. The outer is called the epidermis. It includes epithelial tissue. The middle layer is the most massive, formed by a dense connective tissue of elastic and collagen fibers. This structure allows us to carry out various movements. At the same time, our cover is not torn, but stretched. The deepest layer of the skin consists of dense connective tissue bundles between which fat cells are scattered. Let us consider each of them separately from the perspective of the relationship between structure and functions.
Epidermis
Examining the skin under a microscope, you can find that its outer layer consists of two types of cells. The first are dead and dead. They are tight to each other, forming a stratum corneum. Its cells are continuously exfoliated. In this case, the skin does not become thinner. What is the secret? Under the stratum corneum of the epidermis is germ. Its cells are constantly dividing, providing processes of regeneration - restoration of the skin.
The epidermis determines the color of the skin. In his cells is a coloring matter - the pigment melanin. It is his education that causes summer tanning.
Dermis
The middle layer is called skin or dermis. Examining the skin under a microscope, you can see that it is here that most of its elements are located. These include receptors. These are special sensitive formations that can perceive pain, cold, heat, touch.
The sebaceous glands are located in the dermis, which secrete a special fat. It softens the skin and hair, prevents the penetration of harmful substances into the body. Sweat glands look like glomeruli, the straightened part of which opens outward with an opening. Sweat consists of water with solutions of mineral salts and urea.
Follicles, or hair bags, are also located in the middle layer. They are braided by capillaries, with the help of which there is nutrition and gas exchange. Each hair connects to the muscle that lifts it. This is noticeable in a stressful situation. Under the influence of the nervous system, the muscles contract, so "the hair stands on end". This reaction is called a piloerection. It has a protective value, since it reduces heat transfer through the skin.
Subcutaneous tissue
This layer of skin is the deepest and most massive. It represents a peculiar supply of nutrients. Their body uses during fasting as a reserve. Subcutaneous fat is also involved in heat transfer, protecting the body from hypothermia. Fiber plays an important role in mechanical damage. In everyday life, we do not notice this, but to step on the feet is possible only thanks to a layer of subcutaneous fat. Do not believe? And you try to walk on your knees, the cups of which do not have such protection. This will be difficult to do due to strong friction and pain.
So, the skin under the microscope is a unique structure. It is formed by epithelial and connective tissue, which consist of several layers: the epidermis, dermis and skin. The structure of each of them corresponds to the functions performed.