1) The human body is built from four types of tissue: connective, epithelial, muscle and nerve. According to Raven, Evert & Eichhorn (1986), connective tissue is the main pillar of the body. It makes up human skeleton and connects various tissues and organs; moreover, it protects them from damage. Connective tissue consists of cells of various types, usually located far from each other, and their need for oxygen and nutrients are generally small. Comparing functions of connective and epithelial tissues, it is possible to say that the last tissue also has its main function to protect various organs from mechanical damage and infection. It is a fact that some areas of our body have stratified squamous epithelium and other areas have simple squamous epithelium, and such situation has a place because some external and internal surfaces of human body needs more protection than others. Muscle tissue, in contrast to previously observed tissues, is a type of tissue that carries motor processes in human body (for example, blood flow through blood vessels, the movement of food in digestion, etc.) with special contractile structures – the myofibrils. And at the end, nervous tissue consists of nerve cells – neurons and neuroglia. In addition, it contains the receptor cells and exactly nerve cells can transmit electrical impulses.
2) Environmental hazards, intense ultraviolet radiation, chemicals, pharmaceuticals, nerve transfer and not in the least improper cosmetics upset the balance of the skin. Understanding different roles and functions of four different membranes (physical barriers), it is possible to say that their damage will destroy the work of the whole organism because human skin will be unprotected in this case. James, Berger & Elston (2005) mentioned that the main role of physical barriers is reproduction of cells and protection against external influences.
3) Tattoo is a design on the skin, obtained by introducing the dye into the skin through punctures of its surface. DeMello (2000) stated that tattoos are permanent because they influence on the deeper layers of the skin and impact on hypodermic tissues. Henna tattoos are different from ‘traditional’ tattoos in the way of their putting on human skin, because Henna tattoos are made in special way without damaging of skin.
4) Skin Cancer is generalized name of malignant epithelium of the skin. Usually, it includes all malignant neoplasms of epidermal origin: basal cell carcinoma or cancer that develops from basal cells of epidermis; squamous cell carcinoma (squamous cell carcinoma); melanoma (a neoplasm of neuroectodermal origin). Basal cell carcinoma is the most popular type of skin cancer. It is emerging in the basal layer of the epidermis. The tumor is characterized by slow growth and is treatable. It may grow into surrounding tissues, destroying them. Remote metastases are rare. The tumor often develops in those parts of the body that are regularly exposed to solar radiation, for example, on the face and hands. Squamous cell carcinoma, in contrast to basal cell carcinoma, develops from the squamous epithelium. The tumor is usually solitary; it may be placed on any parts of the body. It is different from basal cell carcinoma by its rapid infiltrating growth and ability to metastasize. It is spread mainly by lymphogenous way. This type of cancer is the most common to people with dark skin and it usually begins in places not exposed to the sun (leg, foot). Thinking about melanoma, we can say that melanoma is formed in melanocytes (pigment cells). Most melanocytes are located in the skin. Melanoma can appear anywhere on the skin. In men it most often occurs on the head, neck, the shoulders and hips. The women have it on the skin of shins, the shoulders and hips. Melanoma often develops in people with dark skin. If this happens, it is usually located under the nails of hands, legs, hands or on the bottom of feet. According to James, Berger & Elston (2005), melanoma is the most deadly type of skin cancer.
5) There is no doubt that the hypodermis, sebaceous and sweat glands, nails and hair play an important role in maintaining normal physiological condition of the skin. Raven, Evert & Eichhorn emphasized that hypodermis protects the body from excessive cooling, protects it against external irritants or trauma; it is the depot, in which fat stores are deposited, expended in the event of sickness, hunger, and pregnancy. Human skin performs excretory function with the sweat glands, while sebaceous glands secrete a secret, called sebum, which softens the skin, giving it elasticity. Nails protect the tissue of nail bed from various environmental stimuli, while hair protects the head from overheating and from hypothermia. For instance, vellus hair is involved in touch, eyelashes protect the eyes, hair in nose and ears retain dust. Lastly, hair and nails are mostly made of keratin (a type of protein), which forms also the outer layer of human skin.
DeMello, M. (2000). Bodies of Inscription: a Cultural History of the Modern Tattoo Community, California. Durham NC: Duke University Press.
James, W., Berger, T. & Elston, D. (2005). Andrews’ Diseases of the Skin: Clinical Dermatology (10th ed.). Saunders.
Raven, P., Evert, R. & Eichhorn, S. (1986). Biology of Plants (4th ed.). New York: Worth Publishers.