Histology para-ail tract

Question 1

Function of the salivary glands?

Answer 1

1. Secrete digestive enzymes
2. Lipids and proteins enhance enamel
3. Lysozymes prevent bacterial growth
4. IgA secretion for defense

Question 2

Function of the salivary glands?

Answer 2

1. Secrete digestive enzymes
2. Lipids and proteins enhance enamel
3. Lysozymes prevent bacterial growth
4. IgA secretion for defense

Question 3

What are the smallest types of ducts

Answer 3

Intercalated ducts, myoepithelial cells

Question 4

What are the larger ducts?

Answer 4

Striated ducts, columnar cells with basal striations

-basal have mitochondria to concentrate the saliva

Question 5

Which gland provides the most content for saliva?

Answer 5

Submandibular gland

Question 6

What do ducts secrete?

Answer 6

Bicarb and mucins and water

Question 7

What do acinar cells secrete?

Answer 7

Enzymes

Question 8

What makes up the maj of pancreas?

Answer 8

Acinar cells

Question 9

Polarized acini

Answer 9

Basal: RER (basophilic)
Apex: zymogen granules (eosinophilic)

Question 10

How is the pancreas protected from the enzymes it makes?

Answer 10

1. Makes proenzymes
2. Produces trypsin inhibitors
3. Tight jxns between acini prevent leakage

Question 11

What activates enzymes ?

Answer 11

Enterokinase of the brush border cells activate panc enzymes via trypsinogen–trypsin

Question 12

Which enz are sec in active from?

Answer 12

Amylase and lipase

Question 13

What are hepatic cords?

Answer 13

• Max blood-heptocyte interface
• Fenestrated endoth sep blood from hepatocytes
• hepatocytes sep by sinusoids

Question 14

Describe polarity of hepatocytes

Answer 14

• polarized along many surfaces
• apex=bile canaliculi
• basal=sinusoids

Question 15

Describe the flow of blood into the liver

Answer 15

Portal vein and hepatic artery–>mix in sinusoids–>hepatic venules–>IVC

Question 16

Describe the classic hepatic lobule structure model

Answer 16

Hexagon of portal tracts with a portal vein in the center

Question 17

Describe the hepatic acinus structure model

Answer 17

Portal tracts on top, central veins on the bottom. Blood flows from tracts to veins. Bile flows from around veins to tracts

Question 18

What do zone 3 hepatocytes do?

Answer 18

Lipid, drug, alcohol detox

Question 19

What layers is the gallbladder made of?

Answer 19

Epithelial, lamina propria and muscular prop only (1 layer)

Question 20

What makes bile?

Answer 20

• bile salts
• conjugated bilirubin
• cholesterol
• phospholipids
• electrolytes
• water

Question 21

What are bile salts?

Answer 21

• Synth from cholesterol by hepatocytes and conjugated in the SER
• Bacteria can unconjugate bile salts
• If conjugated, bile salts are reabsorbed in the small intestine
• Form micelles
• Amphipaths

Question 22

What prevents back diffuse of bile salts into hepatocytes?

Answer 22

Before secretion into bile, carboxyl side chains are conjugated with taurine or glycine within hepatocytes.

This produces stronger acids, which ionize the small intestine and prevent back diffusion of bile salts into the bile ducts and intestine. Ileal receptors bind conjugated bile salts

Question 23

Ursodeoxycholic

Answer 23

Secondary bile acid ursodeoxycholic has OH in beta position → more H2O soluble

Question 24

Protective mechanisms from unconjugated bilirubin?

Answer 24

Unconjugated bili is neurotoxic; protective mechanisms: binding to albumin, blood brain barrier, conjugation, excretion in bile; all protective mechanisms may be somewhat defective in newborn

Question 25

IgA

Answer 25

Some of it is in the bile

Question 26

Epithelium of the gallbladder

Answer 26

Simple columnar secretory epithelium

Question 27

Valves of Heister

Answer 27

Within the cystic duct from which the fundus and head of the gall bladder emptied

Question 28

What causes contraction of the gallbladder?

Answer 28

CCK

Question 29

Sphincter of Oddi

Answer 29

in the ampulla of vater, cck causes relaxation so bile and panc contents can be sec into duodenum