What Am I Riddles

Question: What demands an answer, but asks no question?

Question: What is one in every doll, in every doll, in every doll?

Question: What is it that no man wants, but no man wants to lose?

Question: I'm heavy but not backwards.

What am I?

Question: It breaks away from its pack. It creates holes in its victims. It can travel for miles and then disappear. It is part of a dying breed. What is it?