Epithelial Glands II Flashcards
Exocrine gland
duct persists
Endocrine gland
duct does not persist
secretes into capillaries
Compound gland
multicellular gland divided into subunits called lobules
Lobule
equivalent to simple branched gland
Secretory units of lobule
tubular, alveolar (acinar), or tubuloalveolar
Paranchyma
components of the gland derived from epithelium
Stroma
connective tissue capsule surrounding the entire gland as well as connective tissue that partitions separating the lobules and lobes
Septa (trabeculae)
extensions of capsule (stroma) that divide lobes and lobules
Lobes
subdivision of a compound gland separated from adjacent lobes by septa
Lobules
- subdivision of lobe
- separated by septa
- equivalent to simple, branched gland
Acinus
- secretory components of a lobule
- serous, mucous, or sero-mucous
- basement membrane covers outer surface of acinus
Myoepithelial cells
- found between basement membrane and secretory cells of acinus
- derived from epithelium but are characterized by extensive actin bundles resulting in contractility
- help to express the secretions of the acini into the intercalated ducts
3 different kinds of ducts
- intralobular ducts
- interlobular ducts
- lobar ducts
Intralobular ducts
- ducts that lie WITHIN a lobule
- two types: intercalated ducts and striated ducts
- joined by the confluence of 2+ interlobular ducts
- lined with columnar epithelium transition into stratified columnar epithelium
Intercalated ducts
- drain the secretory acini
- lined by simple squamous epithelium transition to low cuboidal epithelium
- involved in bicarb/Cl- exchange
Striated duct
- lined by cuboidal epithelium transitioning to columnar epithelium with basal striations (for active transport)
- ACTIVELY reabsorbs sodium ions, passively reabsorbs chloride ions, ACTIVELY secretes potassium ions
Interlobular ducts
- formed by confluence of 2+ striated ducts and are found in the septa between adjacent lobules (found in connective tissues)
- lined with pseudo stratified columnar epithelium
- between lobules inside a lobe
Lobar ducts
- formed by confluence of 2+ intralobular ducts
- lobar ducts are lined with stratified columnar epithelium
Minor salivary glands
- line oral cavity
- include Von Ebner’s glands, labial glands, palatal glands, buccal glands
- keep surface of oral cavity moist
Major salivary glands
include parotid, submandibular, and sublingual glands
Parotid glands
-composed only of serous acini
Submandibular glands
- mixed glands with both mucous and serous acini, but serous are predominant
- serous secretory cells form a crescent-shaped configuration around the mucous acini; these are called serous demilunes
Sublingual glands
-mixed glands but the mucous acini are predominant
