The surface of the skin of the scalp, which is the protective physical barrier and site of hair growth, is approximately 600 cm2. Hair is made up of keratin and is very strong. On the head of an adult, there are about 100-000 hairs.
SCALP: PHYSICAL BARRIER AND HEAT INSULATOR
The scalp is composed of soft tissues that cover the skull and is a continuous, soft, durable outer layer. This layer can be divided into several more layers. The layer closest to the surface of the head contains the hair follicles. In fact, the structure of the skin of the scalp is no different from the structure of the skin on other parts of the body. It performs various functions: it provides physical, barrier, immune protection, thermal insulation … As a rule, the process of cell renewal of the scalp takes 2 weeks. However, in the presence of inflammation, this process can be accelerated. The process of renewal of skin cells in other parts of the body takes longer – 3 weeks instead of 2. Dead skin cells of the hairy part of the voice crumble in the form of tiny scales. In case of inflammation and excessive flaking, dead cells stick together and become visible. These associations of dead cells are called dandruff.
HAIR: HIGH STRENGTH
The main function of hair is to protect the head. The visible part of the hair, protruding above the surface of the skin, is called the “hair shaft”. The part of the hair located under the skin is called the “root”. The hair shaft grows from the root, which is located in the hair follicle. The hair follicle is the “production unit” of the hair. Every day, our hair follicles produce millions of new keratinocytes. These cells synthesize keratin, a fibrous structural protein that is the main component of the hair and makes it extremely strong. At the bottom of the hair follicle is the hair papilla, which contains several small blood vessels that supply the nutrients and oxygen needed for hair growth. Above this papilla is the sebaceous gland, which produces sebum. Thus, the hair is constantly lubricated. The hair shaft consists of three parts: the medulla, surrounded by a cortical layer, which is covered by the cuticle. Hair color depends on the individual characteristics of the person. On average, an adult human head grows from 100 to 000 hairs.