1Your Incredible Living Shield
Have you ever thought about what keeps your insides in and the outside world out? Your skin is a bustling, living shield that never takes a day off! It is actually made of three main layers, each with a very important job. The top layer, called the epidermis, is the tough part you can see. Below that is the dermis, which holds your sweat glands and hair follicles. At the very bottom is the hypodermis, a layer of fat that keeps you warm and acts like a soft cushion for your muscles. Together, these layers work as a team to protect you from germs, keep you waterproof in the rain, and help you feel the world through the sense of touch.
2The Great 28-Day Makeover
One of the most amazing things about your skin is that it is constantly renewing itself. While you are busy playing or sleeping, your body is hard at work on a "conveyor belt" of cell production. Deep inside the epidermis, brand-new cells are born every single day. These strong, fresh cells slowly move toward the surface, pushing the older cells up. By the time the old cells reach the top, they flake off to make room for the new ones. This whole process takes about 28 days. That means about every month, you are walking around in a completely brand-new set of skin surface!
3Heavy Duty Protection
Your skin is actually the largest organ in your entire body! If you could spread an average adult's skin out flat, it would cover nearly two square metres—that is about the size of a small bed sheet. It also weighs quite a bit, coming in at around four kilograms, which is heavier than a large bag of flour. Because it is so big and important, your body has special ways to fix it if it gets hurt. If you get a deep cut, the body uses a tough fiber called collagen to knit the gap back together quickly. This creates a scar, which is like a permanent, extra-strong patch that keeps your shield solid and safe.
