When we study the levels of organization of the human body, we learn that cells group together to perform the same function. These groups of cells are tissues. These tissues, in turn, group to form a structure responsible for a specific function in a given system. An organ is a structure formed by several tissues. Given these definitions, a question arises: is the skin a tissue or an organ?
The skin, despite its appearance, is an organ, not a tissue. It consists of two main layers, the epidermis and the dermis, which, in turn, are formed by different tissues. Therefore, the skin is an organ because it is formed by more than one tissue.
It is worth mentioning that the skin has a very impressive characteristic: it is the most extensive organ in our body. Studies reveal that 15% of all our body weight comes from the skin. In adults, this organ can weigh up to 10 kilograms.
The skin has multiple functions, being of vital importance for our survival. Among the main functions attributed to it, we can mention the protection of our organism and perception of stimuli. As well as elimination of some products of our metabolism and the control of temperature by releasing the sweat produced by the sweat glands.
The Tissues That Form the Skin
The skin consists of two layers, the outermost layer called the epidermis and the innermost layer called the dermis. In the epidermis, we find epithelial tissue, which is formed mainly by cells called keratinocytes. The types of cells in this layer are responsible for the production of melanin. It is a pigment that is responsible for the color of the skin and protects the organism from harmful sun rays.
Just below the epidermis, we find the dermis, which is formed by a connective tissue. This layer is responsible for ensuring the elasticity of the skin. In addition, this layer contains growths of nerves, blood vessels, hair follicles and glands.
Below the dermis is the hypodermis. This tissue is not part of the skin. It ensures that the dermis is attached to underlying bone and muscle. The hypodermis is formed by a loose type of connective tissue.