Lecture 7 Epithelial Glands Flashcards
How do exocrine and endocrine glands relate
- Exocrine
- down growth stays
- duct
- maintains orginial connection with epithelial layer
- secreted on surface
- Endocrine
- Down growth degraded
- ductless
- isolated
- secreate directly to Blood vessels
- They are epithelial
- out growth in connective tissue
WHat are examples of exocrine glands?
Exocrine glands include salivary glands, mammary glands, sweat glands, sebaceous glands, liver, and pancreas
What are examples of endocrine glands?
Endocrine glands include pituitary, thyroid, pineal, parathyroids, adrenals, gonads, liver, and pancreas.
What does exocrine mean?
secretion of product is transported via duct to the surface or surface of the organ
What dos endocrine mean?
Secretory (product = hormone) is released directly into blood
What does paracrine mean?
Secreation that affects neighboring cells
Ex: growth factors
What does autocrine mean?
secretion affects the cell that released the secretory product
ex: IL-2 secreted by T cells
How are glands classfied?
- Number of cells
- Multicellular
- Unicellular
- Whether or no branching is present
- Simple - NO ductal branching
- Compound - have ductal branching
- Shape of gland
- Tubular “Flat”
- Alveolar (acinar) “erlenmyer”
- Tubuloalveolar
- type of secretion
- serous - watery, enzyme filled
- Mucous - thick, mucin containing secretion
- Mixed (serous and mucous) secretion is a combination
- acinus is typically mostly muscoused capped by serous demilune
- Mechanism of secretion
- Merocrine (eccine)
- secretory product is typicaly stored in membrane bound vesicles and cytoplasm/CM is retrieved with exocytosis/endocytosis
- apocrine
- apical cytoplasm released along with product
- Holocrine
- entire cell is released as part of secretory product
- Merocrine (eccine)
What are examples of unicellular glands?
Goblet cells of intestine and trachea (exocrine)
Mucous cells of stomach (exocrine)
Enteroendocrine Cells (endocrine )
WHat are examples or types of multicellular glands?
Examples are most other endocrine and exocrine glands
What are examples or types of tubular glands?
Striaght: crypts of lieberkuhn in large intestine
Coilded: sweat glands of skin
Branched: Fundic, pyloric, and cardiac glands of stomach
What are examples of Alveolar (acinar) glands?
Meibomian glands of Eyelid
Sebaceous glands of skin
What are types of simple excretory ducts?
- secretory portion
- tubular
- coiled
- tublar branched
- acinar/alveolar
What are types of a compounded (branched) excretory duct?
- Secretory portion
- Branched tubular
- Branched alveolar (acinar)
- Branched tubuloalveolar (-acinar)
What is an example of serous glands?
Parotid salivary gland
What is an example of tubloalveolar (-acinar) gland?
Salivary glands
BRunners glands of dueodenum
Wha tis an example of mixed gland?
Submandibular and sublingual glands
What are the examples or types of glands classified with a mechanism of secretion
merocrine : includes most glands
Apocrine: axillary sweat glands
Holocrine : sabaceous glands
What is the difference between parenchyma nad stroma
Paranchyma = high cellularity
Stroma = CT capsule
What is an acinus
- secretory parts of a lobule
- use any mechnism for secretion
- basement membane covers outer surface of acinus
- Contains myoepithelial cells in its BM and Secretory cells.
- Derevived from epi. T but has extensive actin bundles = contracility
- helps express secretions of acini into intercalated disks
What are intralobular ducts?
- The ducts that lie within a lobule
- two types
- intercalated ducts
- Drained by secretoryacini
- lined w/ simple squamous E. trabsitioning to low cubodial
- bicarbonate/ cl ion exchange
- striated ducts
- Lined by cubodial E to Columnar E with basal striations for active transport
- activley reasorbed Na ions; passivly for Cl; actively secretes K+
What is an interlobular duct?
formed by two or more striated ducts and are found in septae b/w lobules
What are intralobarducts?
formed by joining of two or more interlobular ducts
lined with columnar trasitioning into stratified columnar epithelium
What is a lobular duct?
formed by two or more intralobar ducts
lined with stratidied ecolumnar epithelium
What is the heirarchal structure of a compound gland
Smallest
Acinus -> intercalated or striaghted -> intrerlobular duct - > intralobular duct -> lobular duct
