MH 016 Simple Epithelia

Simple Columnar Epithelium with Goblet Cells

This section of the small intestine is poorly preserved with most of the epithelium detached from the underlying connective tissue.

The surface area of the small intestine is increased by finger-like projections called villi. Examine a villi in which the epithelium is still attached to the underlying tissue.

The epithelium is a single layer of cells that are taller than they are wide. However, this is difficult to see because this section is cut tangential to the surface of the villi. It passes through adjacent cells resulting in multiple nuclei appearing at different levels.

This simple columnar epithelium contains:

• Surface Absorptive Cells (or enterocytes) - their apical surface has tightly packed microvilli to increase their surface area. This is known as a brush border. The dark line underneath the brush border is the terminal web in which the microvilli are anchored.
• Goblet Cells - scattered cells that secrete mucus. The basophilic secretion granules form circular clusters near the apical surface.

The ultrastructure of these two cell types can be seen in EM 034 Small Intestine by transmission electron microscopy.