Jejunum - Slide 128 (cat)
Start with slide 128, a cross section. For identification purposes, note that this section has the villi and goblet cells which immediately signify A small intestine@. Further, there are no submucosal Brunner's glands, so this is not duodenum. There are also no Peyer's patches, which are usually found in the ileum. Find a good straight cut showing the full height of the villi and the true depth of the intestinal glands (crypts).
Look for submucosal (Meissner's) and myenteric (Auerbach's) plexuses: autonomic ganglia containing processes and cell bodies of the parasympathetic system.
What is the functional advantage of having both circular and longitudinal muscle layers in the intestines? Is the outermost coat of the jejunum and adventitia or serosa? Look for the region of the mesenteric attachment.