No it's not, that's an old legend and it has never been proven.
It was proven on Mythbusters. However, it's even been proven outside of Mythbusters. Back in school (quite a while ago, now), I raised this topic with the biology teacher. What was his reply? "Let's test it." Everybody in the class who owned a dog was tasked with collecting a saliva sample. We put them in petri dishes. Then we tested the same number of people's mouths. What did we discover? Exactly what Mythbusters discovered -- there is less bacteria in a dog's mouth than their is in a human's mouth.
Even if you only concern yourself with how much bacteria in a given mouth is dangerous to a human being, the dog's mouth will win out.
Yes, it does. If you consider a moon to be any rocky object of a size smaller than the object that it orbits (and that's really all a moon
is), Earth has more than one moon.
Doctors used to administer, as a cure, lobotomies to patients who were considered crazy. (These "crazies" were probably not actually crazy.)