One organ that we are born with and we see it growing with us entire life is our skin. Do we even realise the changes that it undergoes throughout our lifetime. It is a kind of our first ever self owned body suit through which we start seeing the external world. This so called largest organ of our body is so meticulously designed and scientifically engineered; that we tend to take it for granted when it comes to its protection from pollution, changing temperatures, sunlight, and so many more reasons.
Do you know that our skin as we rightly said is scientifically engineered to constantly renew itself from within to cope with the everyday requirements of our body. It acts as a barrier which is very selective and performs its functions without fail. We normally think that whatever we apply to our skin it enters inside it and shows us the results. But that not true. If it would have been, then simply taking a bath could have quenched our thirst. The point here is our skin is so nicely engineered that if a water molecule cant enter easily the larger ones stand no chance. The selective permeation through the skin, the temperature control, the renewal process of the outer skin, the colour of the skin; everything is a programmed process since our birth. Now we may think why is it so difficult for any substance to enter our skin? Thats only because of the exceptional barrier properties of our skin.
The outermost cover of our skin is very thin but unbelievingly resilient. It is called as stratum corneum. Not only does it holds water but also protects us from various outer micro organisms and prevents us from catching infections. Exactly below this cover there is an amazingly designed little complex pattern of cells stacked together. This is called the epidermis. This layer is very crucial to form a defensive wall against the external temperature variations and internal body. It can for eg withstand freezing cold to extreme desert conditions.