Welcome to my big day! [Squeaks squeaks] Aw, you’re right, Squeaks, it’s not my birthday… But it is the day that I take the bandage off of my elbow!

I was riding my bike the other day, and I had a little spill. Luckily, I wasn’t hurt too badly, but I did get a big cut on my elbow.

So I cleaned out the cut with warm water and soap, and put on a bandage. But check it out! It’s only a week later, and the cut’s basically gone!

That’s because my body—and yours—has a way to to make cuts and scrapes get all better, or heal. Even the ones that bleed. Blood travels through your body in what are called blood vessels.

They’re kind of like straws or tubes. Most blood vessels are long and flexible, which means they’re able to bend. There are lots of really tiny blood vessels right under your skin.

They can be thinner than a single hair! When you get a cut that bleeds, you end up with a hole in your skin that’s deep enough to break some of those tiny blood vessels. It doesn’t take long for your body to figure out that something’s wrong, and it starts to do something to stop the bleeding right away!

Even though blood looks like it’s just one liquid, there are actually a few different ingredients in it. Like platelets, which look like little blobs. They’re way too small for you to see, but there are lots of platelets in your blood, and they start to fill up the hole your cut made in the blood vessel.

They act like a plug to stop any more blood from getting out. Your blood also makes a bunch of stringy fibers, which form a kind of a net, or web. The platelets stick to this web, and to each other, making a lump that completely covers the cut.

After a while, the lump dries out and gets hard. We call this brown, hard lump of platelets and fibers a scab. [Squeaks squeaks thoughtfully] That’s true! A scab is a little like a bandage that the body can grow all by itself!

Under the scab, your body is hard at work, killing any germs that might have gotten inside of your body before the platelets plugged up the cut. Your body also fixes the holes in the blood vessels so that no more blood can leak out, and it starts to close the cut with new skin. As the new skin grows over the cut, the scab starts to get loose.

Once enough of the hole is closed, the scab falls off, and you’re as good as new! Now, for the tough part. Even though it can be hard to do sometimes, leave your scabs alone!

Don’t pick at them, pull them off, or even scratch them. Because the scab has an important job: it keeps germs that are outside of your body from getting inside of your body. If germs get inside of your body, they can cause an infection, which can make the cut hurt much worse.

And if you pull a scab off, you might rip the skin that’s growing over the cut, and your body would basically have to start all over again. After stopping the bleeding, making a scab, and growing new skin, it looks like my body’s all done fixing the cut I got. Hey, Squeaks, wanna go for a bike ride?

Thanks for joining us at SciShow Kids! Do you have a question about your body, or anything else? Find a grownup and ask them to help you leave a comment below, or send an email to kids@scishow.com!