MA - Sirotkin - Exocrine Glands - 2/13 Flashcards Preview

Unit 7 > MA - Sirotkin - Exocrine Glands - 2/13 > Flashcards

Flashcards in MA - Sirotkin - Exocrine Glands - 2/13 Deck (12):
1

What are the three major mechanisms of secretion? Provide a specific example of a gland for each type

1) Holocrine: lysis of cells filled with secretory product Example: sebaceous glands of skin

2) Apocrine: shedding of apical cell segment filled with secretory product
Example: mammary glands

3) Merocrine (called eccrine in sweat glands): exocytosis of proteins or glycoproteins
Examples: sweat glands, salivary glands, exocrine pancreas.

2

What are the differences between simple and compound glands?

Simple glands – single unbranched duct. Secretory portion can be branched or unbranched. Examples: sweat glands and sebaceous glands

Compound glands – multiple branched ducts. Secretory portion can be acinar, tubular, or tubuloacinar. Examples: salivary glands and exocrine pancreas

3

What is the composition of the sebum?

triglycerides, cholesterol, squalene, wax esters

*Clinical correlation: origin of acne.

4

List cell types found in the sweat glands

Pale (clear) cells
Dark cells
Myoepithelial cells

5

What is the function of myoepithelial cells? Where are these cells located?

- Located between basal lamina and secretory or duct cells
- Triangular or elongated nucleus
- Possess long contractile actomyosin-rich processes
- Contraction helps expel secretory product
- Present in sweat, salivary, and mammary glands

6

What are the three types of acini found in the salivary glands? How do their secretions differ?

Types: mucous, serous or mixed

Serous cells: secrete proteins including sIgA and bicarbonate

Mucous cells: secrete mucin (glycoproteins rich in complex carbohydrates)

7

What is the serous demilune? Are the serous demilunes present in the living tissue?

These are mixed acini that are fixation artifacts

8

What is the function of basal striations? In which glands and in what part of a gland are the basal striations found?

Basal membrane infoldings that house mitochondria found in the intralobular ducts of salivary glands

9

How can you differentiate the pancreas from the parotid gland on the histological preparations?

Islets of Langerhans are unique to pancreas

Adipocytes are present in parotid gland

10

What is the content of zymogenic granules?

Digestive proenzymes: lipases, nucleases, amylases

11

Which cells are responsible for producing bicarbonate in the pancreas?

● Intercalated ducts --> protrude into acini as centroacinar cells

● Intralobular ducts --> lack striations (secrete bicarbonate-rich fluid)

● Interlobular ducts --> low columnar epithelium

12

What are the distinguishing features of each of the three salivary glands?

Parotid gland: all serous; note adipocytes

Submandibular gland: mostly serous

Sublingual gland: mostly mucous