Scabs help stop the bleeding from a cut, but what are they made of and how do they form?
The belly button forms just a few weeks after you are born but why do we have them?
Jessi explains why it is we feel bad when we don't get enough sleep.
Have you got freckles? Ever wondered what they are or why some people have them and others don’t?
What causes a cold and how do we get rid of it?