Please enable JavaScript.
Coggle requires JavaScript to display documents.
Glands - Coggle Diagram
Glands
classification
Number of cells
multicellular
unicellular
most common is goblet
respiratory
GI
secrete mucopolysaccharides
single secretory cell located in non-secretory epithelium
relationship to surrounding tissues
endocrine
ductless
have lost original embryonic connections to the epithelial surface
associated with dense vascular network
can act on remote/distant areas
feature junctions and polarity
may occur as...
irregular clumps (pancreas islets)
cords (adrenal gland)
hollow follicle (thyroid)
exocrine
maintain duct with surface epithelium, secrete onto free surface
morphology
simple
ducts do not branch
secretory end pieces (adenomeres) may be branched
tubular
coiled
acinar/alveolar
compound
elaborate branching duct systems
tubular
acinar
tubuloalveolar
secretory pieces (adenomeres) may be organized into lobules and lobes
may be a discrete anatomic structure or organ
secretions
type
serous
watery, proteinacous
rounded nuclei at base, granules at apex
mucus
polysacccharides
flattened nuclei at base
cytoplasm stains pale
mixed (serous + mucus)
lipid
ex. mammary, sebacous
mode
merocrine
secretes by exocytosis
most common
ex. pancreatic granules, adrenals
apocrine
secretes by loss of apical portion of cell (membrane-bound droplet)
ex. milk fat
holocrine
entire cell extruded
ex. sebaceous gland
cytocrine
transfer secretion to another cell or shedding viable cells
ex. melanin, sperm, oocyte
specialized epithelial cells modified into secretory structures
