[img_assist|nid=25|title=Search the Web|desc=|link=node|align=left|width=100|height=99]Ponder, for a moment, how much you know.
How much basic scientific knowledge do you have?
For example, how old is planet earth? The universe? How old are human beings? Why does salt dissolve in water? Why is the sky blue?
Further - how much basic medical knowledge do you have? For example, why are red blood cells red? Are white or red blood cells produced in the bone marrow? How can we exist with only one kidney? Why is sweat salty?