Esophagus, submucosal gland (cross section)
Note that the basal surface of the non-keratinized stratified squamous epithelium is deeply indented by connective tissue papillae.
In oblique section through the epithelium, the connective tissue papillae can look like "islands" (arrows in micrograph), apparently surrounded by epithelium. Beginning students frequently mistake such an appearance for glands.
The esophageal submucosa includes scattered esophageal glands, which may or may occur in any given specimen. When they occur (as in this micrograph), esophageal submucosal glands are quite conspicuous.
Muscularis externa of the esophagus consists of the standard inner circular and outer longitudinal layers of smooth muscle. In this micrograph, muscle cannot be clearly resolved from connective tissue.
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SIUC / School
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Last updated: 7 October 2003 / dgk