Answer:
What can be swallowed, But can also swallow you?
My head bobs lazily in the sun. You think I'm cute. For my face is yellow my hair is white and my body is green.
In marble halls as white as milk, lined with a skin as soft as silk. Within a fountain crystal-clear. A golden apple doth appear. No doors there are to this stronghold, yet thieves break in and steal the gold.
A doctor might remove one from the neck of a Dracula victim.
When I live I cry, If you don't kill me I'll die.
What goes up the hill and down the hill, And spite of all, yet stand still?