The skin is the human body and of transcendental importance largest organ. It is our outer shell and its basic function is to separate the body from the environment. The skin is a large organ, for estimated roughly an area of about 2 m 2 and a weight of 4 kg, which is approximately 6% of total body weight. In this post we will explain the main features and know a little more structure.
From the shallowest to the deepest, is distributed in three fabric layers with a different embryological origin:
The epidermis is a multilayered keratinizing squamous epithelium and which covers the entire body surface. It is the layer of skin with more cells and a dynamic extraordinarily large parts. The cells grow from inside (basal layer) to the outside (layers corneas). It has a variable thickness (0.1 mm to 1 or 2 mm in the palms and soles).
Da support structure to the skin and provides strength and elasticity. It consists basically of fibroelastic connective tissue. The extracellular matrix contains a high proportion of fibers, not compacted, for collagen (> 75%), elastin and reticulin. It is a vascularized tissue that supports the epidermis and food. It is the largest mass of the skin and its maximum thickness is about 5 mm.
Here it is where we find nerve endings responsible for touch and pressure.
Phases follicular growth : anagen (90% of hairs are in this phase): growth, 2-5 years; catagen: involution, 2-5 weeks; telogen: growth, 2-5 months.
Infundibulum empties the contents excreted by glands:
It consists of loose connective to be secured to anchoring mode. When these bridges are lost, resulting in the typical wrinkles. It consists of adipose tissue, through which run vessels and nerves. Subcutaneous tissue serves store energy as well as thermal insulation and mechanical protection.
Given the structural complexity of the skin, we should know that all topical treatments and active only penetrate the epidermis, particularly in the outermost layers (layers corneas), and who fail to pass the DEJ nor the basal layers . That does not mean that they have effect because the nutritional support and contribution is of great importance for these layers with higher cell replication. Thereby they get these cells to grow healthier and not suffer oxidative stress, basic step for dermatological effect.
Anyway, if the content or the action of the product we want to act in deeper layers, we should use invasive techniques (injections, for example).