Exocrine glands areglands that secrete substances onto anepithelial surface by way of aduct.[1] Examples of exocrine glands includesweat,salivary,mammary,ceruminous,lacrimal,sebaceous,prostate andmucous. Exocrine glands are one of two types of glands in the human body, the other beingendocrine glands, which secrete their products directly into thebloodstream. Theliver andpancreas are both exocrine and endocrine glands; they are exocrine glands because they secrete products—bile andpancreatic juice—into thegastrointestinal tract through a series of ducts, and endocrine because they secrete other substances directly into the bloodstream. Exocrine sweat glands are part of the integumentary system; they have eccrine and apocrine types.
Exocrine glands contain a glandular portion and a duct portion, the structures of which can be used to classify the gland.[1]
The duct portion may be branched (called compound) or unbranched (called simple).
The glandular portion may betubular oracinar, or may be a mix of the two (called tubuloacinar). If the glandular portion branches, then the gland is called a branched gland.
Apocrine – the apical portion of thecytoplasm in thecell membrane, which contains the excretion,buds off. Examples are sweat glands of arm pits, pubic region, skin around anus, lips and nipples;mammary glands, etc.
Seromucous glands (mixed) secrete both protein and mucus. Examples include thesalivary glands: although theparotid gland (saliva secretion 25%) is predominantly serous, thesublingual gland (saliva secretion 5%) mainly mucous gland, and thesubmandibular gland (saliva secretion 70%) is a mixed, mainly serous gland.
^abcYoung, Barbara; O'Dowd, Geraldine; Woodford, Phillip (2013).Wheater's Functional Histology: A Text and Colour Atlas (Sixth ed.). Elsevier. p. 95.ISBN978-0702047473.LCCN2013036824.