Histology Of Accessory GI Glands

Question 1

What are the 3 main Digestive Glands

Answer 1

1. Major Salivary Glands = associated with the oral cavity (parotid, Sublingual, Submandibular)
2. Exocrine Pancreas = alkaline and enzymes into the duodenum
3. Liver = Endocrine and Exocrine gland, access to blood

Question 2

What is the organization of the Salivary Glands

Answer 2

CT tissue over it

Septa divides the gland in to lobes and smaller lobules

Question 3

How are secretory cells in the salivary glands organized and how do they release

Answer 3

Organized into Acinus and make saliva

ANS and Myoepithelial cells control release

Question 4

Order that the saliva travel trough to be released from gland
And type of cell it has

Answer 4

ACINUS—-> (ball shaped, Pyramidal)
intercalated duct——> (low cuboidal)
Striated Duct——> (simple cuboidal—-> simple columnar)
Excretory Duct (simple cuboidal —-> pseudostratified columnar + stratified columnar)

Question 5

Parotid Gland Features

Answer 5

Serous Gland (serous secretory cells)
Largest salivary gland, prominent RER(basal) + secretory granules (apical)

Question 6

Submandibular Gland

Answer 6

Serous Cells mostly, some Mucous cells
Mucous cells: acini are capped by serous demilunes (bonnet)
shorter intercalated ducts
Longer striated ducts

Question 7

What acini are capped by serous demilunes (bonnet)

Answer 7

Mucous Acini

Question 8

Sublingual Gland

Answer 8

Mucous Acini mostly however some Serous 
Tubular branched glands 
No capsule, divided into lobes 
Poor intercalated and striate ducts 
You can see some Skeletal Muscle

Question 9

Intralobular duct

Answer 9

Size of the acini

Question 10

The Pancreas is mostly what type of gland

Answer 10

EXOCRINE, has endocrine also
EXOCRINE: make and secrete enzymes for digestion to the duodenum
ENDOCRINE: make and secrete Hs (Insulin and Glucagon) to blood = regulate glucose,lipids,protein metabolism

Question 11

What type of acini glands do the Exocrine Pancreas have
How is it organized
What does it secrete

Answer 11

SEROUS acinus (pancreatic acinar cells)
The CENTROACINAR CELL inside the acinus starts the intercalated duct (low cuboidal) = secretes HCO-3, NA+, H2O (Alkaline)
all cells (except centroacinar and the intercalated duct stain dark)

Question 12

Parotid vs exocrine pancreas

Answer 12

Has BVs

Has controacinar cells

Question 13

What makes a Pancreatic Acinar Cell

Answer 13

Well developed RER + Golgi
ZYGOMOGEN GRANULES (proenzymes)

Question 14

Name the proenzymes that the granules of exocrine pancreas release

Answer 14

1. Trypsinogen, chymotrypsinogen —-> PROTIENS
2. Amylolytic enzymes(a-amylase)—-> CARBS
3. Lipase —-> LIPIDS
4. Deoxyribonuclease, ribonuclease—-> NUCLEIC ACIDS

Question 15

High carb diet vs high protein diets and enzyme formation

Answer 15

Increases the enzyme needed

EX: high protein = high proteases made

Question 16

ENDOCRINE PANCREASES looks like

Answer 16

The islets surrounded by reticular capsule surrounded by exocrine ducts
From endodermal outgrowth
a, B, g,PP

Question 17

Liver is lined by
And glands are arranged as
And what cell type

Answer 17

Visceral peritoneum (mesothelium)
Arranged as CELLULAR CORDS (not acini)
Hepatocytes
Stores and makes BILE

Question 18

Hepatocytes are shaped as

Answer 18

Large polygonal cells + microvilli

Many lysosomes and sER and Golgi

Question 19

What is bile made of

Answer 19

H2O, 
Bile Salts
Pigments
Phospholipids
Electrolytes 
Cholesterol (very little)

Question 20

Bile function

Answer 20

Fat absorption
Excretion of Cholesterol, Iron, Cu, Bilirubin
Drains into Bile CANALICULUS (between the hepatocytes)

Question 21

Hepatic Lobule

Answer 21

Drains blood from PORTAL VEIN + HEPATIC ARTERY ——> Central Vein or Hepatic Vein (middle of acini)
6 portal triads to central vein

Question 22

Portal Lobule

Answer 22

Drains bile from hepatocytes (from central vein)——> to bile duct
Three central veins to one portal triad

Question 23

Hepatic Acinus

Answer 23

Supplies oxygenated blood to hepatocytes
Two portal triads (when 2 hepatocytes connect) and give blood differently based on how far you are from the central vein of each hepatocyte
*most important for pathology and doctors usually

Question 24

Gallbladder

Color is veryyy green

Answer 24

Stores and concentrates bile
Simple columnar + microvilli over Lamina Propria
Muscularis Externa present in irregular way
NO Muscularis mucosae
NO submucosa
EXTERNAL ADVENTITIA against the liver part (other parts are Serosa)

Question 25

Rokitansky - Aschoff Sinuses (RA sinuses)

Answer 25

Deep diverticuli of the mucosa that can extend all the way to the Muscularis layer
= from hyperplasia, herniation
=bacteria can come here causing chronic inflammation = gallstones