This low magnification
view of the colon shows: 1) the lumen (Lu), containing
fecal matter (F); 2) the mucosa
(Mu), containing crypts of Lieberkuhn (C);
3) the submucosa (Su); and the muscularis
externa (MM) consisting of an inner layer (IL)
and an outer layer (OL) of smooth muscle. The
folding of the submucosa is normal for an empty colon.