Epidermis is the first layer of your skin. It creates cells that travel up to the surface of your skin, it takes around two weeks to travel to the top. The skin that you see is actually dead skin cells. This is also where all the melanin is. Melanin is what makes your skin dark and light. It also gives you your skin sun protection so the darker your skin is the more melanin you have, so the more sun protection you have. But the melanin can't protect you completely, that's why you have hats and sunscreen! ;)
Dermis is the second layer of your skin, it has the blood vessels, the nerve endings, the hair follicles (hair) oil glands and the erector pili muscle. I am sure you all know what blood vessels are but just in case I will tell you, they carry blood through the body. Did you know that when it is cold the vessels shrink so that they keep the warm and when it is hot they grow so that your blood gets more heat. The nerve endings are here because they send messages to the brain and they need to send the sense of feel to the brain in this case.i bet your wondering what the erector pili muscle does it is a very small muscle, what it does is it pulls the hair follicle up straight when your cold and that's why your hair stands up straight when your cold. Oil glands make sebum (sweat) which comes out of holes called pore. Sweat water proofs your skin and keeps it cool and fresh.
subcutaneous fat protects bones, organs and muscles and keeps you warm
how do you get freckles?
genetics and sun
did you know that sometimes identical twins have the same amount of freckles
why does your skin go red when you burnt?
when you get burnt lots of blood goes to that area so it goes red
how come some people cant get tan like others can?
its because the people who can get very tan have more melanin so they have more sun protection so they have enough melanin to get where as if you didn't have enough melanin you would get burnt straight away.
. live science
. kids health website
. the video below