Know about Body Parts (2): 

Skin, Hair

Skin

Skin is the biggest organ in your body. It covers everything that is inside of our body. It acts like our body’s armour, protecting the delicate parts inside our body from dirt, germs, bumps and knocks. Without our skin, all the bones, muscles and organs would be hanging out. The skin holds everything in place. It protects our body and keeps it at the right temperature. It helps us to stay warm in winter and stay cool in summers. It also makes Vitamin D which is very important to keep your bones healthy and strong.  It helps us feel things by touching. We can feel if something is hot, cold, soft or hard. The skin is not only the largest organ; it is also the largest sensory organ of our body. When we touch something, the nerves in the skin send information to our brain. The brain employ this information to indicate back if a bit we have touched is hot, cold, rough, smooth or prickly. It also help us sense pain if something hurts our skin.

            Skin is made of three different layers. The top layer, or epidermis, contains a tough material called keratin, which makes your skin strong. The middle layer is called the dermis. It contains nerve endings that help you feel things, blood vessels that bring food and oxygen to the skin, and glands that make oil and sweat. The bottom layer is fat.

            Skin colour

The cells in our skin produce melanin that gives colour to the skin. So, if the pigment cells in your skin make more melanin, you will have a dark skin colour. In the same way one will have fair skin colour if less melanin is produced by the skin. Some skins produce more melanin than others because melanin has another purpose too. It take up the dangerous ultraviolet rays of the sun. So, people living in hotter climates make more melanin to protect their skin. People living in colder climates don’t need this protection, so they make less melanin and have fair skin colour. But there is another factor that decides our skin colour. It is our genes.

            Our skin build vitamin D when it is uncovered to the sun. This vitamin is very important for making our bones strong and healthy. We don’t need to be in the sun for too long as our body needs only few minutes of sunlight everyday to make this vitamin. Sun is closest to the earth during noon time and this is when the sun rays are strongest. So morning or late in the afternoon is good to have fun in the sun.

Hair

Hair is a protein filament that grows from the follicle in the skin. It grows everywhere on the outer body. Hair makes you to look good as well as having important functions. A number of people have curly hair as of the type of hair follicle they have. Rounded shape follicles make curly hair, while straight follicles make straight hair and oval follicles make wavy hair. Next to each follicle is a gland that makes oil to keep your hair waterproof and shiny.

           

Whether you have straight or curly hair, your hair does an important job. On a cold day, it keeps your head warm, and on a hot day, it protects your head from the sun. Hair acts as a cushion and protects the head from minor bumps. It acts as a cap in winter and gives you warmth. It performs as a shield in summers. It prevents the burning sunrays to fall directly on your scalp.