5.5b – Microanatomy of Pancreas and Salivary Glands

Question 1

What does the gall bladder do?

Answer 1

-stores and concentrates the bile by water absorption and inorganic salt absorption

Question 2

What happens to the empty gall bladder?

Answer 2

-thrown into folds (plicae)

Question 3

Gall bladder epithelium:

Answer 3

-tall simple columnar epithelium that extends into mucosal crypts
>covered by small microvilli and joined by tight junctions
*goblet cells are present in ruminants

Question 4

Gall bladder layers:

Answer 4

-L. muscularis mucosae: absent
-T. muscularis: circularly-arranged smooth muscle fibers
-T. serosa: on free side
-T. adventitia: in hepatic attachment area

Question 5

Secretory units of salivary glands can be:

Answer 5

-serous
-mucous
-seromucous

Question 6

Serous gland example:

Answer 6

-dog parotid gland

Question 7

Mucous gland examples:

Answer 7

-dog and cat mandibular gland
-cattle, sheep and pig sublingual gland

Question 8

Seromucous gland examples:

Answer 8

-horse mandibular gland
-dog and cat sublingual gland

Question 9

What might surround acinar or tubuloacinar units?

Answer 9

-serous demilunes

Question 10

What do serous cells contain?

Answer 10

-zymogen granules

Question 11

What is located between secretory cells and basal lamina of salivary glands?

Answer 11

-myoepithelial cells

Question 12

Intercalated ducts of salivary glands:

Answer 12

-short ducts lined by low cuboidal epithelium
-connect secretory acini with striated ducts

Question 13

Straited (salivary or intralobular) ducts of salivary glands:

Answer 13

-largest structures in lobules
-lined by simple columnar epithelium
-participate in secretory process

Question 14

What do the cells form in striated ducts of salivary glands?

Answer 14

-basal folding containing mitochondria
*basal membrane contains energy-requiring ion-pumps

Question 15

Interlobular ducts of salivary glands:

Answer 15

-located in interlobular connective tissue
-lined by simple columnar epithelium
>changes to striated columnar or cuboidal epithelium

Question 16

Main duct of salivary gland:

Answer 16

-single duct that leaves the salivary gland
-lined by stratified columnar or cuboidal epithelium

Question 17

Pancreas is a _______gland:

Answer 17

-encapsulated
-lobulated
-compound
-serous tubule-acinar
*contains endocrine and exocrine parts

Question 18

Endocrine part of the pancreas produces

Answer 18

-enzymes
>amylase
>lipase
>trypsin

Question 19

Exocrine part of the pancreas produces:

Answer 19

-hormones
>insulin
>glucagon
>others

Question 20

What is the organization of the exocrine part of the pancreas?

Answer 20

-lobules containing intralobular ducts that are NOT striated
-tubuloacinar secretory units with centroacinar cells
>tubular part is more prominent in ruminants
-glandular epithelial cells

Question 21

Glandular epithelial cells of the exocrine part of the pancreas:

Answer 21

-pyramid-shaped cells with spherical nucleus near the base
-have intense basal basophilia containing extensive rER
-apical region: membrane bound-zymogen granules
-Golgi complex between zymogen granules and the nucleus

Question 22

How are the intercalated ducts organized in the pancreas?

Answer 22

-begin in centre of glandular unit
-open into intralobular ducts lined by low cuboidal epithelium
*intralobular ducts are NOT striated

Question 23

Centroacinar cells of the pancreas:

Answer 23

-cells of the duct in the middle of acinus
-insert into acinar lumen
-secrete bicarbonate and water when stimulated by secretin (to raise pH of ingest)
>neutralize acidic gastric contents entering the duodenum

Question 24

Where is secretin released from?

Answer 24

-enteroendocrine cells in the duodenum and jejunum

Question 25

Acinar cells of the pancreas:

Answer 25

-CCK stimulates release of zymogen granule contents

Question 26

What are the contents of zymogen granules?

Answer 26

-trypsinogen
-chymotrypsinogen
-proelastase
-procarboxypeptidase
-pancreatic amylase
-lipids

Question 27

Interlobular ducts of the pancreas are lined by:

Answer 27

-simple columnar epithelium

Question 28

Endocrine part of the pancreas:

Answer 28

-pancreatic islets that are located between exocrine part
-contain A, B, C, D, and F cells
*approximately 75% are B cells that produce insulin
*A-cells produce glucagon