Lecture 9: Epithelial Glands Part II

Question 1

What is the difference between parenchyma, and stoma, and septa?

Answer 1

• The components of the gland derived from epithelium (secretory units and ducts) comprise the parenchyma.
• The connective tissue capsule surrounding the entire gland as well as the connective tissue partitions separating the lobules and lobes comprise the stroma.
• Septa (trabeculae) are extensions of the capsule into the epithelial components of the gland that divide the gland into subdivisions called lobes and lobules.

Question 2

Give the difference between a lobule and a lobe

Answer 2

Lobes: A lobe is a subdivision of a compound gland separated from adjacent lobes by septae.
- Lobules: A lobule is a subdivision of a lobe. Lobules are separated from each other by delicate septae. Each lobule is equivalent to a simple, branched gland.

Question 3

Define an Acinus

Answer 3

• Acini are the secretory components of a lobule.
• Acini may be serous, mucous, or sero-mucous (mixed)
• Basement membrane covers the outer surface of the acinus.
• Myoepithelial cells are found between the basement membrane and the secretory cells of the acinus.
• Myoepithelial cells are derived from epithelium but are characterized by extensive actin bundles resulting in contractility.
• Myoepithelial cells help to express the secretions of the acini into the intercalated ducts.

Question 4

What are intralobular ducts?

What are the two types of intralobular ducts?

Answer 4

• Intralobular ducts are ducts that lie within a lobule.
• Intercalated Ducts
• Striated Ducts

Question 5

Describe intercalated ducts

Answer 5

• Drain the secretory acini.
• Lined by simple squamous epithelium transitioning to low cuboidal epithelium.
• Involved in bicarbonate/chloride ion exchange.

Question 6

Describe Striated Ducts

Answer 6

• Lined by cuboidal epithelium transitioning to columnar epithelium with basal striations (for active transport).
• Actively reabsorb sodium ions; passively reabsorb chloride ions; actively secrete potassium ions.

Question 7

Describe Interlobular Ducts

Answer 7

• Interlobular ducts are formed by the confluence of two or more striated ducts and are found in the septae between adjacent lobules.
• These ducts are lined with pseudostratified columnar epithelium.

Question 8

Describe Intralobar Ducts

Yes, you are officially being fucked with now.

Answer 8

• Intralobar ducts are joined by the confluence of two or more interlobular ducts.
• Intralobar ducts are lined with columnar epithelium transitioning into stratified columnar epithelium

Question 9

Describe Lobar Ducts

Answer 9

• They are formed by the confluence of two or more intralobar ducts.
• Lobar ducts are lined with stratified columnar epithelium.

Question 10

Review Slide 10 on Lecture 9 to make sure you understand the hierarchy of all those ducts and lobes and shit.

Answer 10

Do It!

Question 11

Describe the 4 minor salivary glands and their general function

Answer 11

• Located throughout the oral cavity and include:
• Von Ebner’s glands, labial glands, palatal glands, and buccal glands.
• These glands keep the surface of the oral cavity moist.

Question 12

What are the 3 Major Salivary Glands and give their purpose

Answer 12

• Parotid glands: The parotid glands are composed only of serous acini.
• Submandibular glands: The submandibular glands are mixed glands with both mucous and serous acini, but the serous acini are predominant. Serous secretory cells form a crescent-shaped configuration around the mucous acini; these are called serous demilunes.
• Sublingual glands are also mixed glands, but the mucous acini are predominant.

Question 13

Do NOT neglect those glands. That shit’s gonna hurt if you do.

Answer 13

Do IT!