What is the skin?
The skin is an organ of the body, the largest organ of all. Unlike other organs like the stomach and intestines, the skin is on the outside of the body. It protects the inside of our bodies from germs, dirt, cold and heat. It’s also waterproof, stopping us from soaking up everything and getting all soggy inside! Best of all: it heals itself. Isn’t that amazing? If we cut our skin, the skin will get straight to work making new skin for us. If you look at it like that, we’re kind of like superheroes!
Skin and temperature
The skin keeps all our muscles and organs at the right temperature, around 37ºC, it’s like a natural coat. Imagine how cold our muscles would feel on a winter's day, and how dry and wrinkly they would get on a hot summer's day.
When we’re hot the skin opens its blood vessels, this lets blood reach the surface of the skin where it can cool down and release heat. Has your face ever gotten red after running or exercising? That’s the red blood vessels of the skin. Our bodies will also start to sweat to release body heat. When the sweat evaporates from our skin it cools us down.
When we’re cold the blood vessels get smaller to keep warm blood away from the surface of the skin. When this happens, little muscles in the skin pull on the hairs of the body making them stand up giving us goosebumps.
Keep it clean
The skin is our natural coat that we have to keep clean regularly. Washing every day with mild soap makes the skin feel happy and stops any nasty bacteria from growing on it. Drinking plenty of water gives the skin a good shower from the inside, keeping it extra clean and shiny!
- A rhinoceros’s skin can be up to 5 cm thick.
- Polar bears have black skin, it’s just their hair which is white.
- The palms of the hands and the soles of the feet have the thickest skin of all.
- Frogs soak up water through their skin rather than drinking it, they also use their skin to absorb air.
- A snake’s skin might look wet and slimy, but it’s actually dry and smooth.
- Too much sun can damage the skin.