Question

What is the function of skin?

Answer 1

Hint: The skin is part of an integumentary system which is an organ system, and consists of skin, hair, nail and exocrine glands. They are a few millimetres thick. It provides additional protection to the body. It covers the outermost part of the human body.

Complete answer:
Skin is by far the largest organ in the body. It has a surface area of about 20 square feet. about $15\%$ of body weight is contributed by skin. It has coloured pigments. The different shades of skin we see around are actually the coloured pigments which give it different colours. Ranging from ar melanin, melanoid, carotene, haemoglobin and bilirubin.
The skin protects us from microbes and other pathogens, it helps us in regulating body temperature, also it permits the sensation of touch, cold and heat.
Talking about the skin, is comprise of two main layers which are as follows:
The outermost epidermis: made of closely packed epithelial cells it provides a waterproof barrier and creates our skin tone.
Dermis: it has two layers-
The inner dermis which is made of dense irregular connective tissue. It houses blood vessels, hair follicles, sweat glands, and other structures.
Beneath the dermis there lies the hypodermis. It is composed mainly of loose connective and fatty tissue.
Primary function is to protect from external barriers. It helps us in regulating body temperature, also it permits the sensation of touch, cold, pain and heat. It absorbs vit D.

Note:
Human skin shows a very high skin colour variety. When humans secrete sweat, it also contains some amount of urea, hence it is the secondary function of temperature regulation. It is a dry and semi-impermeable barrier to fluid drain.