Explain the functions of a mammalian skin

1. Protection
The body is protected by the skin in many ways. The melanin in the skin protects it from harmful UV rays. Keratin, a type of protein found in the skin, helps promote elasticity and supports the structure that forms the skin. The skin protects organs, inner tissues and even bones from being exposed to the outside world. More exact examples are protection against sun damage, physical trauma and bacterial invasion.
2. Temperature Regulation
When you become hot, your skin releases sweat from the sweat glands to help cool you down. The tiny blood vessels in your skin can also fill with blood when you are cold, making you warmer. The release or retention of heat depends on temperature outside of the body. This is one of the crucial functions of the skin.
3. Immunity
Certain cells in the skin work closely with the immune system to fight off bacteria, viruses and other nasty things that land on your skin. The skin prevents them from getting into your body and making you sick. Those cells include epidermal dendritic cells, phagocytic cells and langerhans cells.
4. Permitting Movement and Growth
The elastic properties of the skin and the tissues underneath it allow your body to grow and change. They also make it much easier to move. If your skin were rigid and hard, you would suffer pain when moving, if you were able to move at all. The recoil properties of the skin mean that it bounces back to its original form, without leaving “dings and dents” in your body.
5. Excretion
Your body needs to get rid of the waste products somehow. Some of these wastes can be excreted through the skin, such as urea, water, uric acid and ammonia. This helps rid your body of the things that might make you sick if your skin didn’t serve as a gateway to the outside.
6. Endocrine
This function lies in the synthesis of Vitamin D. On the list of functions of the skin, your skin does a marvelous job of absorbing Vitamin D from the sun, and then turning it into something your body can use. An organic chemical in your skin reacts with the sunlight and gives you this essential vitamin. Be careful not to get too much sun, because some harmful rays can cause sunburns and possibly skin cancer later in life.
7. Sensation
Your skin can be very sensitive and allow you to feel the slightest changes in temperature, pressure and the like. Nerve endings in your body react to the sensations the skin feels, alerting your brain to the new feeling in an instant. This means you can react to hot or cold, to pain or injury, and even to a gentle touch in the appropriate manner.
8. Absorption
Your skin actually “breathes.” You can absorb oxygen, nitrogen and other necessities through your skin. Though you still need your lungs to breathe, some animals have skin so advanced that they can actually take in all the air they need through the skin. The cells on the outside of your skin are affected by the amount of oxygen in the room; this is why you are encouraged to let your skin “breathe” by wearing cotton clothing and the like.
9. Water Resistance
The skin serves as a barrier to water. This is important because it prevents your body from losing all the necessary nutrients and minerals that it stores up. The outer skin is covered with oils and nutrients that form a natural barrier against water.
10. Other Functions
There are more functions of the skin. It prevents the evaporation of the water in your body by forming a barrier that keeps it all inside. It also serves as a complex storage center for lipids and water; sometimes skin will swell as a result of the water inside the body, especially during times of illness of injury. That water is eventually reabsorbed, and only the skin keeps it from being evaporated.

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Arnold Diru answered the question on June 22, 2018 at 21:37