Finger-like villi (asterisks) project into the lumen of the small intestine. Embedded in the lamina propria are numerous simple tubular intestinal glands, also known as the crypts of Lieberkühn (green arrows). These glands open at the base of the villi where they deliver intestinal juice into the intestinal lumen (boxed area). Beneath the lamina propria, the smooth muscle layers of the muscularis mucosae can be identified (Mm). A distinctive feature of the duodenum is the presence of submucosal or Brunner’s glands (red arrow).
Jejunum Villus+Goblet Cells 400X
Intestinal absorptive cells, the enterocytes (asterisks), mixed with goblet cells (green arrows) form the epithelial lining of each villus. Enterocytes absorb and transport digested substances from the intestinal lumen to capillaries located in the lamina propria. Microvilli (pink arrow) can be seen as a brush border on the luminal surface of the enterocytes. Enzymes associated with the microvilli complete the digestion of most sugars and proteins. Observe that the goblet cells are in varying stages of mucous production. Lymphoid cells and lacteals can be identified in the connective tissue of the lamina propria (Lp).
Colon Mucosa Mucous Stain LS 40X
The longitudinal section shows intestinal glands or crypts of Lieberkühn (arrow) in the thick mucosa of the large intestine. Openings of the crypts on the luminal surface are visible. A mucous stain was used to elucidate mucin-secreting goblet cells in the glands. The continuously secreted mucin lubricates the intestinal contents. Vast numbers of darkly stained lymphoid tissues appear in the lamina propria. The inner circular and outer longitudinal smooth muscle layers of the muscularis mucosae (Mm) are represented by red and black asterisks, respectively.
Rectal Mucosa Goblet Cells 400X
The crypts of Lieberkühn or intestinal glands of the rectum contain the greatest number of mucin-secreting goblet cells (asterisks) found in large intestine intestinal glands. Although not apparent in the section, the ratio of goblet cells to absorptive cells (arrows) is about 1:1. Lymphoid and fibroblast cells can be identified in the lamina propria.
OTHER IMAGES AVAILABLE WITH THE BOOK AND
CD-ROM
Esophagus Internal Wall 40X
Esophagus Outer Wall 40X
Esophagus Muscularis Externa + Adventitia 40X
Esophogastric Junction 40X
Stomach Mucosa Cardiac Region 40X
Stomach Mucosa Fundic Region 40X 100X
Stomach Gastric Glands Fundic Region 400X
Stomach Pyloric Region 40X 100X
Stomach Pyloric Glands 400X
Stomach Body Wall 40X
Duodenum Mucosa + Submucosa 100X
Duodenum Brunner’s Glands 400X
Duodenum Villi 100X
Jejunum Villi 100X
Jejunum Intestinal Glands 100X
Jejunum Intestinal Glands + Paneth Cells 100X 400X
Ileum Mucosa Mucous Stain 40X
Ileum Parasympathetic Ganglion 400X
Caecum Mucosa Rabbit 40X
Caecum Parasympathetic Neurons Rabbit 400X
Vermiform Appendix Mucosa 40X
Colon Mucosa Mucous Stain LS 100X
Colon Goblet Cells 400X
Colon Intestinal Gland 400X
Colon Wall 40X
Rectum Mucosa Rectal Folds 40X
Rectum Parasympathetic Ganglion(Myenteric Plexus) 400X
