The tiny protuberances that line the small intestines are called villi and microvilli.
well, it depends on what you compare it to of how you interpret the word's meaning. :)
Mostly plankton, minute organisms.
pretty tiny
No, snakes are legless. some salamanders called Sirenians have two residual hind legs some two forelegs, they are wholly aquatic, and do resemble serpentine animals.