Astonishingly, human skin is the largest organ in our body. Though it’s not our internal body organ unlike our heart, brain or lungs, or any internal body organ. We wear our skin outside. An adult carries skin layers around 8 pounds around 3.6 kilograms and 22 square feet which is almost 2 square meters long. Our skin performs many functions rather than just making us look presentable. The flexibility of our skin ables us to move freely and perform different tasks and run daily errands with ease.
Our skin protects us from microbes and the elements which can harm us. It also protects us from infections. Our skin also helps in regulating our body temperature and lets us feel sensations of touch, heat, and cold. Our skin protects us from a barrier between the external environment and the internal organs. Our skin has the ability to be strong, powerful and it can heal itself. Human skin has basic three layers of tissues.
1-Epidermis The Stratum Corneum
The epidermis is the outer layer of the body that gives the primary protection to us and acts as the primary barrier to our inner body. It is made of cells called “Keratinocytes”, the same tough protein material which we experience in our hair and nails. Keratinocytes form several layers that constantly grow outwards as the exterior cells die. They replace the flaky dead outer layer of the skin constantly. Scientific research tells us that it takes almost five weeks for newly created cells to work their way to the surface.
The surface of most human skin is soft to touch. Our skin has a diversified texture in many areas of our body. As on our elbows and our knees, our skin is wrinkled and a bit rough. On our eyelids, the skin is thinnest, whereas on our palms and feet soles the skin is thickest. This is a fibrous layer that strengthens and supports the epidermis. Its thickness varies in different areas of our body as mentioned above.
This guards our immune system against harmful infections too. It is the thickest layer of the skin and it is made up of fibrous and elastic tissue. Keratin is a protection naturally found in human skin. This protein creates a water-resistant barrier to protect epithelial cells from coming into contact with harmful substances. Since keratin is insoluble. It is incapable of being dissolved in water. One more fact about our skin is that if direct heat of more than 10 minutes is applied to the skin, it can crack open, because of fat in the skin it is a lot like candle wax.
2- The Dermis
The epidermis also has a deeper layer called the “Dermis“. The dermis is the layer of skin that lies beneath the epidermis and above the subcutaneous layer. It gives our body the required strength and elasticity to perform our bodily functions with ease. There is a network of blood vessels in it which helps in regulating our body temperature, increasing the blood flow and also it controls the extreme fluctuation situations by hot and cold water, weather or conditions.
The receptors and nerves in this layer help us feel sensations such as touch, cold, hot, pain and transmit any signal it receives from outside of our body or throw sensory recipients to our brain. The dermis has hair follicles and gland ducts in it too.
Sweat glands, through perspiring, bring the body temperature down. It also causes body odor, especially in human armpits. The oil-like sebum in this re-lubricates our hair and skin.
3- Subcutaneous Layer
This is the deepest tissue of our skin, which is called the “Subcutaneous layer“. It’s made up mostly of fat cells and connective tissue which is beneath the dermis and which supplies nutrients to the dermis.
It is also called the base layer of the skin. The fat in this layer works for us when due to adverse situations, there is a scarcity of food and gives us a chance to survive in such conditions.
It also protects our bones and muscles from any dangerous injuries due to falls or knocks, in case if it happens accidentally.
The main functions of our skin are:
- Human skin controls our body temperature
- Human skin regulates blood storing
- Human skin protects us from outside factors which can destroy our health, such as bacteria infections, and toxins, extreme weather conditions, damage from sun rays, etc.
- Human skin helps us to feel sensations, as skin is a huge sensor full of nerves and receptors.
- Human skin helps to produce Vitamin D for healthy bones.
- Human skin Absorbs and extracts the required fluids and substance.
As we know that the human body is made of 60% water approximately. According to biological chemistry experts, the human brain and heart are composed of 70% to 73% of water, and human lungs are composed of around 82% to 83% of water. Human muscles and kidneys are composed of 79% of water, whereas in bones the composition of water is 30% to 31%. And the skin contains 64% of water.
Skin thickness also varies in men and women. A women’s subcutaneous fat layer is almost twice as thick as that in men. Men have most of the fat in their abdomen around their organs. However, the amount of fat in women’s skin also depends on their body weight and ethenic origin.
The skin is the most important organ. Without it we can just evaporate in no time as all muscles, bones, and organs within the human body will be hanging out of place completely. The skin color in our skin is because of melanin, which is a pigment produced by the epidermis which protects us from sunlight exposure, basically from ultraviolet rays, which can cause skin cancer. Dark skin color is basically found in people in tropical regions, whereas fair complexion is mostly found in those who live in the Northern latitudes. But of course, the mix of races and migration and many other factors determines the skin color of people in any region.