Glands

Question 1

Glandular epithelium

Answer 1

• Secretory cells of the exocrine or endocrine glands
• Formed by the proliferation of surface epithelial cells into the underlying connective tissues

Question 2

Formation of exocrine and endocrine glands

Answer 2

Forms by the proliferation of cells and their downgrowth into the subjacent connective tissues

Forms secretory portion

Question 3

Difference between exocrine and endocrine glands

Answer 3

Exocrine Glands always attached to surface epithelium by duct system whereas endocrine glands become detached from surface epithelium in formation when duct cells as lost

Question 4

Endocrine Glands

Answer 4

• Multicellular glands that do not have a ductal system
• Secretory products are hormones
• Secretion is released into the intercellular fluid and then carried by the blood and lymph.

Question 5

Exocrine glands

Answer 5

• Mostly multicellular glands with a ductal system
• Ducts carry secretions into the sites of utilization
• Two types:
  1. Simple glands- one or more secretory units connected to a simple duct
  2. Compound glands- many secretory units connected to a complex ductal system

Question 6

Simple vs. compound exocrine cells

Answer 6

1. Simple glands- one or more secretory units connected to a simple duct
2. Compound glands- many secretory units connected to a complex ductal system

Question 7

Parenchyma

Answer 7

Both glandular epithelium, ductal system, and the stroma

Question 8

Purpose of stroma

Answer 8

Made of connective tissues and used to hold the ductal system

Question 9

What are glands made of?

Answer 9

Two types. Might contain just glandular epithelium OR parenchyma

Question 10

Secretory units in glands

Answer 10

• Acinus (small and narrow)
• Alveolus (large and distended)

Question 11

How are large glands divided?

Answer 11

1. Lobes
2. Lobules

Question 12

What are within lobules?

Answer 12

Lobules contain secretory units.

Glands contain secretory units called acinus (small and narrow) or alveolus (large and distended)

Question 13

Myoepithelial cells (contractile cells)

Answer 13

Cells that exhibit the characters of both muscle and epithelium, found at the base of the secretory cells/units

Help release the secretion into the duct when contracted in response to stimulus

Question 14

Are there unicellular or multicellular glands?

Answer 14

Both!

There are either unicellular glands (eg. Goblet cells found among epithelial cells lining the gastrointestinal tract and respiratory tract lumen) or multicellular glands

Question 15

How are glands classified?

Answer 15

Based on morphological characteristics, nature of the secretory product, and the mode of release of the secretory product

Question 16

Classification of simple glands

Answer 16

All branches are directly attached to duct
- Simple tubular
- Simple coiled tubular
- Simple branched tubular
- simple acinar
- branched acinar

Question 17

Classification of compound glands

Answer 17

Branches come off branches that are attached to the duct
- compound tubular
- compound acinar
- compound tubuloacinar

Question 18

Different types of secretory products of glands

Answer 18

1. Serous
2. Mucous
3. Seromucous

Question 19

Serous

Answer 19

• Typically towards base or side
• Thin watery product, contains zymogen granules (precursors of enzymes)

Eg. Parotid gland
Eg. Exocrine pancreas

Question 20

Mucous

Answer 20

Thick and viscous mucin, contains mucinogen (precursor of mucin)

Eg. Salivary gland

Question 21

Seromucous

Answer 21

Contains serous, mucous or seromucous secretory units
Can see serous demilunes.

Eg. Parotid gland
Eg. Sweat glands

Question 22

Mode of release of the secretory products of glands

Answer 22

• Merocine (eccrine)
• Apocrine
• Holocrine
• Cytocrine

Question 23

Different duct types within a ductal system

Answer 23

1. Intercalated duct (simple cuboidal)
2. Intralobular duct or striated ducts (simple cuboidal)= Striated due to abundance of mitochondria (need energy for active transport)
3. Interlobular duct (stratified cuboidal). Might have stratified columnar epithelium

Question 24

Duct branch order

Answer 24

1. Interlobular duct- close to surface; stratified cuboidal
2. Intralobular duct/striated ducts- lots of mitochondria because need energy; simple cuboidal
3. Intercalated ducts- simple cuboidal