Question

Nothing!

Answer 1

what do you know about plicae circulares or villi? where are they? how do they look like?

Answer 2

what do you think @IsaacLightsey31

Answer 3

post that in a new thread please :)

Answer 4

http://prntscr.com/6xpmgr
pay very close attention to structures and labels
you will see where is and how plicae circulares looks like as well as how and where villi is located and looks like

Answer 5

http://ect.downstate.edu/courseware/histomanual/digestive.html
Go to Jejunum section and read it through
not to be confused
read http://en.wikipedia.org/wiki/Circular_folds
the section 'Composition'