Atlas of Plant and Animal Histology

Animal tissues.
Glandular epithelium.


This image is from respiratory ducts.
Cursor over de the pig to see where the image comes from.
Organ: lung, respiratory ducts, exocrine gland
Species: pig (Sus scrofa domesticus; mammal)
Technique: PAS-haematoxylin, 8 µm thick section, paraffin embedding.

Exocrine glands show an excretory duct, which connects the secretory units (in red) with the free surface of the epithelium. The morphology and arrangement of both secretory and excretory parts result in a wide variety of exocrine glands (see table). Compound exocrine glands show branched excretory ducts, branched glands show several secretory units releasing to a single excretory duct, and simple exocrine are not branched at al and has one secretory unit. Regarding the secretory units, exocrine glands are known as tubular, acinar, or alveolar, depending on the organization and morphology of the secretory cells. The gland in the image above looks like a branched gland (but not compound), because several secretory units can be seen, but just one unbranched secretory duct.

Updated: 2016-01-18. 18:03