Lect 36 & 37- Digestive Glands and Liver

Question 1

what does the delicate CT of the pancreas contain

Answer 1

blood vessels, lymphatics, nerves, and excretory ducts

Question 2

what is the main excretory duct in the pancreas

Answer 2

duct of wirsung

Question 3

what is the small accessory duct in the pancreas

Answer 3

duct of santorini

Question 4

what are interlobular ducts of the pancreas lined with

Answer 4

simple columnar epithelium and goblet cells

Question 5

what are intercalated ducts of the pancreas lined with and what cells are in there

Answer 5

lined with low cuboidal cells: cells with receptors for secretin and that secrete water and bicarbonate ion

Question 6

what do plasma cells in the parotid gland of the pancreas secrete

Answer 6

immunoglobulin A

Question 7

what do the centroacinar cells of the pancreas form

Answer 7

form a truncated epithelium within the lumen of acini that is continuous with the epithelium of the intercalated duct (unique to pancreas)

Question 8

what is the release of digestive enzymes from serous acinar cells stimulated by

Answer 8

CCK

Question 9

what are bicarbonate-rich alkaline fluids released by and in response to what

Answer 9

released by ductal epithelial cells in response to secretin

Question 10

how are synthesis and secretion of digestive enzymes in pancreas controlled

Answer 10

by peptides secreted by duodenal enteroendocrine cells

Question 11

what is the secretion of bicarbonate ions in the pancreas regulated by

Answer 11

secretin

Question 12

describe A cells (alpha cells) of the islets of langerhans

Answer 12

have fine cytoplasmic granules and are presumed to form glucagon

Question 13

describe B-Cells (beta cells) of the islets of langerhans

Answer 13

have coarse cytoplasmic granules; they are more numerous than alpha cells and produce insulin

Question 14

describe D-cells (delta cells) of the islets of langerhans

Answer 14

secrete somatostatin, which helps to control levels of insulin and glucagon

Question 15

what does the space of disse do

Answer 15

separates hepatic cells from endothelial cells

active in transfer between blood and parenchyma

Question 16

what is then space of mall continuous with

Answer 16

space of disse

Question 17

what does the space of mall drain into

Answer 17

lymphatics

Question 18

describe classic hepatic lobules

Answer 18

central venule is in the center of the lobule

portal triads are at the angles

Question 19

describe portal hepatic lobules

Answer 19

three central venues of adjacent lobules forms a triangle

portions of the bile canaliculi of the 3 lobules drains into the same bile duct

Question 20

describe the liver acinus hepatic lobules

Answer 20

includes 3 zones defined by hepatic tissue receiving blood form a branch of the hepatic artery conducting blood to opposite central veins
metabolic gradient extends from hepatic triad to central vein

Question 21

what happens in zone one of the hepatic lobule

Answer 21

hepatocytes actively synthesize glycogen and plasma protein. oxygen concentration in sinusoidal blood is high

Question 22

what happens in zone 3 (central venous drainage) of hepatic lobules

Answer 22

it is the region where oxygen concentration is poorest. it has a role in detoxification. hepatocytes are susceptible to damage caused by hypoxia

Question 23

where is the portal triad found

Answer 23

at angles (corners) of classic lobule

Question 24

what are the components of the portal triad

Answer 24

branch of hepatic artery (arteriole)
branch of portal vein (venule)
bile duct (ductule)

Question 25

what does the limiting plate of the hepatocytes surround

Answer 25

portal space

Question 26

what types of fibers are found in the space of disse

Answer 26

1, 3, and 4

Question 27

define canal of hering

Answer 27

terminal point of the network of bile canalicular trenches found on the hepatocyte surfaces. located at the periphery of the hepatic lobule and connects with the bile ductules in the portal space after perforating the limiting membrane

Question 28

describe the basolateral domain of a hepatocyte

Answer 28

microvilli faces space of disse involved in absorption of blood-borne substances and secretion of plasma proteins

Question 29

what does the apical domain of hepatocytes border

Answer 29

bile canaliculus

Question 30

what type of epithelium is in the canal of hering

Answer 30

squamous to cuboidal simple epithelium

Question 31

what is the lining of the hepatic sinusoids like

Answer 31

fenestrated with endothelial cells | discontinuous basal lamina

Question 32

where are perisinusoidal cells located and what do they do

Answer 32

located in space of desse store vitamin A produce collagen fibers and extracellular matrix components

Question 33

what happens to perisinusoidal cells during cirrhosis

Answer 33

they transform into myofibroblasts and become the main collagen type 1 producing cells (stimulated by cytokines form hepatocytes, kupffer cells and lymphocytes)

Question 34

what does the sub endothelial space of disse contain

Answer 34

microvilli of basolateral domain of hepatocytes type 1, 3, and 4 collagens interstitial fluid that drains into the space of mall that drains into lymphatics

Question 35

what are characteristics of kupffer cells

Answer 35

phagocytic cell derived from monocytes lines hepatic sinusoids

Question 36

what does the bile canaliculus receive

Answer 36

bile from hepatocytes

Question 37

what does the canal of herring do

Answer 37

receives bile from canaliculus | carriers bile to bile ductule

Question 38

what does blood coagulation depend on that is produced in the hepatocyte

Answer 38

fibrinogen, prothrombin, factor VIII

Question 39

what do complement proteins do (ER in hepatocytes)

Answer 39

synthesized by hepatocytes, participate in destruction of pathogens

Question 40

what do the mucosal folds of the neck of the gallbladder form

Answer 40

the spiral valve of heister

Question 41

what is the epithelium in the mucosa of the wall of the gallbladder

Answer 41

epithelium is tall columnar with a striated border

Question 42

describe the lamina propria of the mucosa of the wall of the gallbladder

Answer 42

has extensive vascular plexuses and may contain a few smooth muscle cells

Question 43

small diverticula of the mucosa which extend into the muscular and perimuscular layers and may indicate pathological change

Answer 43

rotikansky-aschoff sinuses

Question 44

describe the serosa of the wall of the gall bladder

Answer 44

has a broad perimuscular CT coat, rich in blood and lymphatic vessels and elastic fibers

Question 45

what does the gallbladder release bile in response to

Answer 45

cholecystokinin stimulation (produced by enteroendocrine cells in the duodenum) and neural stimuli together with relate of the sphincter of Oddi

Question 46

define sphincter of oddi

Answer 46

muscular ring surrounding the opening of the bile duct in the wall of the duodenum

Question 47

what is the mucosa of the ducts lined with (liver/gallbladder?)

Answer 47

columnar epithelium with goblet cells

Question 48

where is alcohol oxidized to acetaldehyde (ethanol met)

Answer 48

in the cytoplasm

Question 49

where is acetaldehyde converted to acetate (ethanol met)

Answer 49

in mitochondria

Question 50

what is catalase

Answer 50

major protein of peroxisome that decomposes H2O2 into H2O. it is a tetramer of apocatalase molecules assembled within peroxisome

Question 51

what does TNF-alpha do during chronic liver diseases

Answer 51

causes a slow down and arrest of the flow of nine in nine ducts

Question 52

what is transforming growth factor beta secreted by

Answer 52

kupffer cells and hepatocytes

Question 53

what releases interleukin-6

Answer 53

kupffer cells

Question 54

what are the bile components

Answer 54

cholic and chenodeoxycholic acid (synthesized by hepatocytes) deoxycholic acid and lithocholic acid (converted by bacteria) water and electrolytes cholesterol and phospholipids pigments and organic molecules

Question 55

what is the major pigment in bile

Answer 55

bilirubin

Question 56

where is conjugated bilirubin secreted into

Answer 56

intestine

Question 57

what is conjugated bilirubin in the intestine converted by and into

Answer 57

by bacterial action into urobilinogen

Question 58

where do bile salts emulsify dietary lipids

Answer 58

small intestine