The pancreas, salivary, and mammory glands

Question 1

What are the pancreatic exocrine subcategories ?

Answer 1

Pancreatic acini
Pancreatic acinar cells
Duct system

Question 2

What are pancreatic acini ?

Answer 2

They are serious acini - secrete a thin fluid rich in pancreatic digestive enzymes.

Question 3

How do acini cells appear?

Answer 3

Their nuclei in the center of the acini.
They represent the beginning of the ducts.

No myoepthethelial cels around the acini.

Question 4

What are pancreatic acinar cells?

Answer 4

Pyramidal in shape. Nuclei are basal.

Cytoplasm ; basal due to part basophillic. - due to abundant RER

apical part acidophilus - due to secretory granules

Question 5

What is the exocrine pancreas duct system?

Answer 5

Centroacinar cells

Intercalated ducts - low cuboidal
Intrlobular ducts - not prominent
Interlobular ducts

Main pancreatic duct

Question 6

What are the islets of langergans?

Answer 6

Pale staining spherical collections of endocrine cells, scattered among the acini.

Question 7

The islets of langerhans are richly vascularised by what?

Answer 7

Fenestrated capillaries

Question 8

What is each islets surrounded by?

Answer 8

Reticular fibres

Question 9

How many islets in a human pancreas ?

Answer 9

1million

Question 10

Where are majority of islets located ?

Answer 10

Tail of pancreas

Question 11

What are the different cells of the islets?

Answer 11

B cells
A cells
D cells
G cells
Pp cells

Question 12

What is the function of B cells?

Answer 12

Secrete insulin which lowers blood sugar.

Constitute 70% of Islet cells

Concentrated in islet center

Question 13

Function of A cells ? Islets

Answer 13

Secrete glucagon which increases blood sugar.

15-20% of Islet periphery.
Tightly packed and more dense granules.

Question 14

D CELLS function?

Answer 14

Secrete somatostatin which lowers the release of hormones from endocrine pancreas and enzymes from exocrine pancreas.

5-10%, scattered throughout islet
Less dense than a and b

Question 15

Function of G cells?

Answer 15

Secrete Gastrin which increases the production of Hcl by the parietal cells of the stomach.

Question 16

PP CELLS function?

Answer 16

Secrete pancreatic polypeptide which lowers exocrine sections from the pancreas.
1% of islet cells
Scattered

Question 17

What are the major salivary glands ?

Answer 17

Paratid
Submandibular
Sublingual

Question 18

Minor salivary glands

Answer 18

Labial (lips)
Lingual (tongue)
Buccal (cheek)
Palatine (palate)

-> produce 5% of salivary output
Most are pure mucous or seromucus glands.

Question 19

General structure of salivary glands

Answer 19

Stroma - CT capsule, CT septa, Reticular CT

Parenchyma - Ancini, duct system

Question 20

3 types of salivary acini

Answer 20

Serous acini
Mucous acini
Mucoserous acini

Question 21

What are serous acini ?

Answer 21

Secrete serous secretion - thin fluid rich in enzymes such as amylase and lysozyme (antibodies to pathogens)

Only contain serous cells
Small spherical with a narrow lumen

Question 22

What are mucous acini?

Answer 22

Contain only mucous cells
Larger more tubular with a wider lumen.

Secrete mucous secretion - thick Viscid secretion and rich in mucin

Question 23

What are mucoserous acini?

Answer 23

Mucous acini with a cap of serous cells. Called serous demilunes

Question 24

What are the shape of the serous cells?

Answer 24

Pyramidal, nuclei round and basal.

Cytoplasm is deeply basophillic due to (numerous RER)

Apical acidophilic secretory granules (rich is salivary amylase)

Question 25

The mucous cells structure?

Answer 25

Pyramidal or cuboidal Nuclei are flattened Cytoplasm is pale basophilic and vacuolated due to dissolved my Oo feb secretory granules.

Question 26

Myoepithelial cells:

Answer 26

Contractile cells that embrace the basal aspect of the acini Their contraction relaseases the secretion into the duct system.

Question 27

3 ducts of the salivary glands

Answer 27

Intralobular ducts Interlobular ducts Main duct

Question 28

What is the Interlobular duct

Answer 28

Lined by simple columnar epithelium

Question 29

What is the intralobular duct ?

Answer 29

Intercalated ducts : lined by small cuboidal cells Striated ducts : formed by union of 2 intercalated ducts (striated due to mitochondria) Lined by low columnar cells - also called the secretory duct because it can change the ion concentration of saliva due to the presence of the ion transporters.

Question 30

Main duct of the salivary gland

Answer 30

Lined by statrifed columnar epithelium which becomes stratified squamous in the distal end.

Question 31

What are the 3 main salivary glands

Answer 31

Parotid gland Submandibular gland Sublingual gland

Question 32

What is the parotid gland

Answer 32

Largest gland Produces 30% salivary output Purely serous Prominent Interlobular ducts Rich section - amylase , lactoferrin, lysozyme, secretory igA

Question 33

Submandibular gland

Answer 33

Produces 60% of salivary output Mixed but mostly serous (90%) Produces alpha amylase and lysozyme Mainly contains Mucous acini which are capped by serous demilunes.

Question 34

Sublingual gland

Answer 34

Smallest 5% of output Mostly mucous Mucous acini are capped by serous demilunes

Question 35

What does ingestion of food do?

Answer 35

Stimulates the release of saliva via parasympathetic innervation.

Question 36

What causes dry mouth?

Answer 36

Strong sympathetic innervation (xerostomia)

Question 37

What gland is the mammory gland ?

Answer 37

Compound tubulocinar gland

Question 38

What cells assist the secretion of milk from acini

Answer 38

Myoepithelial cells

Question 39

What is let down?

Answer 39

Contraction of Myoepithelial cells under control of oxytocin

Question 40

Apocrine secretion in the mammory gland

Answer 40

Non membrane bound lipid pushes through the plasmalemma. Covering droplets with membrane and a thin layer of apical cytoplasm. Membrane becomes transiently smaller needed information addition of extreme membrane Other milk constituents; lactose proteins and minerals are released by merocrine secretion