Exocrine Glands Flashcards
Outline of the Exocrine Gland
Possesses exocrine portion and secretory portion
Exocrine portion of the gland is also called the
duct
Glands are classified by
whether they are simple (unbranched) or compound branched
Organization of the Exocrine Gland
Capsule
Septa or trabeculae, which organized interior into lobes or lobules
Lobule
Contains the following
Acinus (the secretory portion+excretory portion)–> intercalated duct —>
striated duct—>
intralobular duct
the above constitute the interior of the lobe
Acinus secretory glands have three types of secretions
mucous (glycoproteins), serous (water + proteins), and serous-mucous.
Serous glands include
merocrine (eccrine)
Mercocrine (eccrine)
no part of the secretory gland is lost during secretion
include most glands
(pancrease, salivary, and mammary glands)
Apocrine
Some of the cell is lost during secretion, parts of the apical domain form the vesicle around the lipid/protein product
examples are axillary sweat glands
mammary glands
Holocrine
entire cell is lost during secretion, sebaceous glands (yuck)
Classification of exocrine glands include
1) what is released (glycoproteins or water + proteins) and 2) how they are released (merocrine, apocrine, and holocrine)
Acinus refers to the
secretory part of the gland
Acinus is contained within the
basement membrane
Acinus cells are composed of
myoepithelial cells
Acinus is the
epithelial origin with extensive actin bundles (contractility)
Sequence of cell types within the gland beginning with the acinus
myoepithelial cells (acinus)—>intercalated duct (squamous to low cuboidal)—>striated duct (cuboidal—>columnar epithelium w/basal striations)—-> interlobular duct (pseudostratified columnar epithelium)—-> Intralobar duct (columnar to stratified columnar)—> lobar duct (stratified columnar epithelium)
Duct pattern (example is salivary glands)
acinus–>intercalated—>strat—>intralobar—>interlobar—>lobar
Intercalated ducts
intralobular duct
squamous to low cuboidal
exchange Cl- for HCO3
Striated ducts
an intralobular duct
low cuboidal to columnar w/basal striations
basal domains are accumulations of mitochondria
critical in active transport
converts saliva to a hypotonic state
Secretes lots of potassium, absorbs lots of sodium
Interlobular
ducts BETWEEN lobes in a capsule
pseudostratified columnar
Intralobar
columnar –> stratified columnar epithelium
lobar duct
stratified columnar epithelium
Main duct
is the main duct
Submandibular glands possess what features
1) Serousmucous secreting cells containing the demilune
demilune
the “crescent moon” shapped cap on serous mucous secreting cells in the submandibular gland
What type of cells will we find in the submandibular gland?
both mucous secreting and serous secreting acinus cells
parotid gland: what kind of cells do we expect to find
entirely serous secreting cells
the sublingual gland consists of what kinds of cells
largely mucous secreting acinus
