MA Flashcards
formation of exocrine glands and their components
formation: form as invaginations of epithelium but still have a connection to the surface known as a duct
components: secretory portion (acinus of cells) and conducting portion (duct)
classification of glands
- single-cell
- simple (single unbranched duct and branched or unbranched secretory portion that’s tubular or acinar)
- compound (multiple branched ducts and acinar, tubular or tubuloacinar secretory portion)
types of secretion
- holocrine: lysis (ex: sebaceous glands on skin)
- apocrine: shedding of apical cell segment (ex: mammary glands)
- merocrine/eccrine: exocytosis of proteins or glycoproteins (ex: sweat glands, salivary glands, exocrine pancreas)
serous cells of salivary glands
secrete proteins, stain with H&E and has secretory granules in the apical cytoplasm
mucous cells of salivary glands
secrete mucins, made of glycoproteins and complex carbs, satins with PAS and has mucin-filled secretory granules in the apical cytoplasm
myoepithelial cells of salivary glands
located in the basal lamina along with secretory or duct cells with long actomyosin-rich processes which contract to help expel secretory product
*in sweat, salivary and mammary glands (merocrine cells)
what type of gland is a goblet cell?
mucin-secreting unicellular gland
3 types of multicellular simple glands
- sebaceous glands
- eccrine sweat glands
- apocrine sweat glands
sebaceous gland
- spherical or pear-shaped
- simple branched acinar differentiated from sebocytes
- holocrine secretion
- associated with hair follicles
- origin of acne
apocrine sweat glands
- simple coiled glands
- lined by simple cuboidal to columnar epithelium
- axillary, areolar, perineal regions
- MEROCRINE and phermone secretion
- associated with hair shafts
- stimulated by adrenergic fibers of the SNS
eccrine sweat glands
- simple coiled/tubular
- stratified cuboidal epithelium
- stimulated by cholinergic fibers of SNS
- 3 cell types: pale cells (secrete fluid), dark cells (secrete proteins), myoepithelial cells (triangular nucleus and contracts to expel products)
salivary glands
- a-amylase for carb digestion
- lysozyme, lactoferrin and sIgA for immune defense
- Ca2+ and P to protect teeth through pellicle formation
- PNS stimulates, SNS inhibits
- septa divides parenchyma into lobules which contain salivons (acini, intercalated ducts and interlobular ducts)
draining of acini
acini–> intercalated ducts (no secretory vesicles, cuboidal)–> intralobular ducts (inside lobules, columnar, active transport of ions and sIgA)–> interlobular ducts (in septa, stratified cuboidal to columnar epithelium)
sIgA secretion
dimeric IgA is secreted by plasma cells while serous cells and intralobular ducts have IgA receptors which mediate transcytosis of IgA into gland lumen and then sIgA is formed when the IgA and receptor complex is acted on by proteolysis
3 multicellular compound glands: salivary gland types
- submandibular
- parotid
- sublingual
submandibular gland
- compound tubuloacinar
- serous (secretes proteins), mixed and mucous acini
- *-striated intralobular ducts
parotid gland
- compound acinar
- serous acini (secretes a-amylase)
- *-intercalated ducts are long and abundant
- abundant adipose tissue
- striated intralobular ducts
sublingual gland
- compound tubuloacinar
- *-primarily mucous acini
- intralobular ducts are not striated
exocrine pancreas vs. endocrine pancreas
exocrine:
- compound acinar gland
- secretory products: digestive proenzymes activated by enterokinase and bicarbonate which neutralizes stomach acid for an optimum pH for pancreatic enzymes
- creates protease inhibitors
endocrine:
-islets of Langerhans
what does septa contain?
blood vessels, lymphatics, nerves and ducts
adenocarcinomas
malignant tumors of glandular epithelia
what is the stroma made up of?
septum (separates lobules) and capsule (surrounds gland)
sebum composition
triglycerides, cholesterol, squalene and wax esters
serious demilune
in mixed acini of sublingual and submandibular glands and secretes lysozymes