Definition – What is the dermis?
The dermis is one of the largest human organs, the skin, and is therefore vital. As in every mammal, the skin consists of different layers – one of which is the dermis. It is precisely this layer of skin that is tanned in the leather production process that gives the skin its name.
The dermis is located between the hypodermis and epidermis and is firmly attached to the epidermis. It is responsible for the supply of the epidermis, since it has no blood vessels. Therefore, the dermis contains lymphatic vessels for immune defense as well as blood vessels.
Furthermore, the dermis contains the most hair roots, sebaceous and sweat glands. Furthermore, receptors for the sense of touch are anchored in the dermis. A characteristic of the dermis is its elasticity and tear resistance, which it owes to its large number of collagen fibers.
Function of the dermis
The dermis alone mechanically fulfills various tasks by giving the skin its stability, tear resistance and elasticity. In this way, the skin forms a stable barrier against pathogens that want to penetrate the body. Furthermore, the dermis has an important function in regulating body temperature.
This is achieved by the expansion of the papillae in heat and their contraction in cold. By expanding, they give off heat and by contracting, heat can be stored. It is only through this mechanism and the activation of the sweat glands when it is hot that the temperature is balanced and thus overheating or hypothermia of the body is prevented.
The sweat glands located in the dermis are distributed very differently over the body. Most sweat glands are located on the palms of the hands and feet, as well as in the armpits. In addition, the dermis is responsible for supplying the epidermis, as it has no blood vessels.
The papillae in the dermis are responsible for this nutrient transport. The dermis is also an important link in the chain of the body’s immune defense. It participates in the body’s defensive reactions and thus also in the fight against various pathogens.
The dermis also forms a mechanical barrier. However, if too much force is applied, for example in accidents or falls, the skin tears open. A laceration or graze is the result.
