Exploded view of a cross-section of gut to depict the enteric nervous system (ENS). Structures shown (from internal to external) include the villi, mucosa, submucosal (Meissner's) plexus, circular layer of muscle, myenteric (Auerbach's) plexus, longitudinal layer of muscle, serosa, and neural input and out put from the perivascular nerves and paravascular nerve in the mesentary.