Exocrine glands

Epithelia in which all the cells are specialized for secretion are usually organized as the secretory portions of exocrine glands, which are continuous with the epithelia of ducts through which the secreted product is discharged.

Glands are classified based on the structure of both the ducts and secretory portions.

• Ducts can be branched (compound) or unbranched (simple)

• The overall shape of the glands’ secretory portions can be tubular, acinar (rounded), or tubuloacinar (tubular with a rounded end)

• The secretory portion may also be described further as branched tubular or coiled tubular (i.e., long and not branched)

Study the following examples of glands in some of these structural classifications.
 

Class of gland	Example
Simple, tubular	Lining of large intestine
Simple, coiled tubular	Sweat glands of skin, example 1  and  example 2
Simple branched acinar	Sebaceous glands of skin, example 1  and example 2
Compound, acinar	Exocrine pancreas
Compound, tubuloacinar	Submandibular salivary gland, example 1  (PAS-Alcian blue stains mucus purple) and  example 2