Skin is very important organ and infact, very vital organ of body. Skin is the only organ out of the rest of the other body organs which covers the largest surface area of human body and this is the reason why it is called largest organ of human body. It is the largest organ of human body of the rest of the other organs of body due to its highest surface area coverage of human body.
So, now you know that skin is considered or known as largest organ of human body but do you know what functions skin performs in human body to keep you healthy? If you do not know, then do not worry, this article is filled with all information about functions of skin. So here come the functions of skin which it performs in human body to keep you healthy-
1. Thermoregulation.
2. Acts as Blood store or blood resource.
3. Protection.
4. Vitamin D synthesis.
5. Cutaneous sensations.
6. Excretion.
7. Absorption.
1. Thermoregulation-
Yes, you heard it right; skin does play a very important and vital role in maintaining thermoregulation of human body. Now question comes, what does the term ‘thermoregulation’ mean? The term ‘thermoregulation’ means maintaining homoeostatic balance of human body temperature within normal range. That is skin helps in maintaining normal temperature of human body through its two different but efficient mechanisms. First mechanism is sweat production, which it uses in hot summer days, in heated surroundings or when body produces lot of internal heat during exercise or workout and also in cold winter season and cold surroundings. Now, question is how sweat production help in maintaining body temperature within normal range in both different types of hot and cold extreme environmental conditions?
It does this by controlling amount of sweat production in both different environmental conditions. Sweat evaporation from skin helps in lowering body temperature. So, more the sweat evaporates, more the body temperature gets lowered. So, only thing needed to be taken care of in both the different environmental conditions by human body itself is to control amount of sweat production which skin knows how to taken care of. Skin controls the amount of sweat production in both different environmental conditions. Skin produces large amount of sweat from eccrine sweat glands in hot, humid and high temperature environmental conditions. So, large amount of sweat gets evaporated from skin surface which lowers human body temperature to large extent.
In winter season, skin not only maintains human body temperature but also prevents it from getting lowered by controlling the amount of sweat production. Skin produces less amount of sweat from eccrine sweat glands in winter season, so therefore, less sweat evaporates from skin and therefore, less temperature is lowered from normal body temperature range and therefore, normal body temperature is prevented from getting lowered and is maintained in normal range.
So, this was first mechanism, which helps in controlling and maintaining normal human body temperature. Second mechanism which helps in maintaining normal human body temperature is heat release or in other words heat loss that occurs through flow of blood flowing or running through blood vessels present in dermis of skin. Now, how this controls thermoregulation that is how it maintains normal human body temperature. Skin does this by controlling internal diameter of blood vessels. In summer season and in hot, humid and high environmental temperature conditions, diameter of blood vessels get little increased that is lumen of blood vessels become wider in diameter, they dilate in width. More width, increased diameter of blood vessels means, more blood is flowing through blood vessels, which leads to more heat loss through them and therefore more the temperature gets decreased from high body temperature range which was earlier present there.
Whereas in winter season, blood vessels become narrow, that is their diameter get decreased and therefore, lesser is the amount of blood flowing through them and lesser is the amount of heat loss that occur through lesser blood flow and which ultimately lead more heat conservation and less heat loss. This conserved heat further helps in maintaining human body temperature and prevents it from getting lowered and in this way helps in maintaining human body temperature in normal range.
2. Blood store or blood resource-
Skin is known as blood store or blood resource because it contains huge amount of blood which is running through the large network of blood vessels present in dermis of skin. A lot of blood vessels present there in dermis of skin.
3. Protection-
Skin acts as a barrier which protects the tissues underneath from injuries, harmful substances, chemicals and also from heat. Skin cells named Keratinocytes are tightly interlocked in skin prevents entry of microbes and bacteria and viruses. Fatty layer formed over skin surface by lipid released from lamellar granules forms a waterproof sheet which prevents the entry of water from outside and also prevents evaporation of water from skin tissue and thus prevents skin from dehydrating. Sebaceous glands present in skin secrete oily sebum which nourish the skin and hairs and prevents them from drying out and makes the skin surface smoother. This sebum not only nourishes the skin and hairs but also have antibacterial properties like acidic pH of sweat which kill bacteria and different microbes at skin surface. But, if any how some microbes or disease causing pathogens enter the skin, then the immunological cells like epidermal langerhans and macrophages phagocytize them, that is kill them there and also eliminate them from body. Melanocytes present in skin guard and protect skin tissue from harmful effects of ultraviolet light of sun.
4. Vitamin D synthesis-
Skin also performs function of vitamin D synthesis with the help of ultraviolet rays of sun. These ultraviolet rays of sun activate the precursor molecule of vitamin D in skin and enzymes present in liver and kidney act on this activated molecule and ultimately produce Calcitriol which is the active form of vitamin D.
5. Cutaneous sensations-
Skin contains nerve endings and receptors in its tissue which help human brain in recognizing various sensations for example touch, pressure, pain, heat and cold because nerve endings and receptors respective to these sensations are present in skin.
6. Excretion-
Skin also performs the function of excretion though not at large level like kidneys and liver. It only performs it at a small or you can say at miniature scale. Although stratum corneum is waterproof in nature but water is still lost from skin in the form of sweat along with releasing heat, salts, carbon dioxide, ammonia and urea.
7. Absorption-
Skin also performs function of absorption at small scale and not like large scale of digestive system. The various substances which skin is able to absorb are vitamins A, D, E and K which are fat soluble in nature and therefore are easily absorbed by skin. Other substances which are absorbed through skin are some drugs, respiratory gases like carbon dioxide and oxygen and certain toxic substances like organic solvents, salts of lead, mercury, arsenic and poison ivy and poison oak and certain steroids due to their fat soluble nature which are easily crossed through the fatty layer of skin formed by lamellar granules.
So this was all about what functions skin performs to keep you healthy. But Do You Know Everything About Structure of Nail?