Lect 36 & 37- Digestive Glands and Liver Flashcards Preview

histology (E1 Woods) > Lect 36 & 37- Digestive Glands and Liver > Flashcards

Flashcards in Lect 36 & 37- Digestive Glands and Liver Deck (58)
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1
Q

what does the delicate CT of the pancreas contain

A

blood vessels, lymphatics, nerves, and excretory ducts

2
Q

what is the main excretory duct in the pancreas

A

duct of wirsung

3
Q

what is the small accessory duct in the pancreas

A

duct of santorini

4
Q

what are interlobular ducts of the pancreas lined with

A

simple columnar epithelium and goblet cells

5
Q

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

A

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

6
Q

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

A

immunoglobulin A

7
Q

what do the centroacinar cells of the pancreas form

A

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

8
Q

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

A

CCK

9
Q

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

A

released by ductal epithelial cells in response to secretin

10
Q

how are synthesis and secretion of digestive enzymes in pancreas controlled

A

by peptides secreted by duodenal enteroendocrine cells

11
Q

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

A

secretin

12
Q

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

A

have fine cytoplasmic granules and are presumed to form glucagon

13
Q

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

A

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

14
Q

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

A

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

15
Q

what does the space of disse do

A

separates hepatic cells from endothelial cells

active in transfer between blood and parenchyma

16
Q

what is then space of mall continuous with

A

space of disse

17
Q

what does the space of mall drain into

A

lymphatics

18
Q

describe classic hepatic lobules

A

central venule is in the center of the lobule

portal triads are at the angles

19
Q

describe portal hepatic lobules

A

three central venues of adjacent lobules forms a triangle

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

20
Q

describe the liver acinus hepatic lobules

A

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

21
Q

what happens in zone one of the hepatic lobule

A

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

22
Q

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

A

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

23
Q

where is the portal triad found

A

at angles (corners) of classic lobule

24
Q

what are the components of the portal triad

A

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

25
Q

what does the limiting plate of the hepatocytes surround

A

portal space

26
Q

what types of fibers are found in the space of disse

A

1, 3, and 4

27
Q

define canal of hering

A

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

28
Q

describe the basolateral domain of a hepatocyte

A

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

29
Q

what does the apical domain of hepatocytes border

A

bile canaliculus

30
Q

what type of epithelium is in the canal of hering

A

squamous to cuboidal simple epithelium

31
Q

what is the lining of the hepatic sinusoids like

A

fenestrated with endothelial cells

discontinuous basal lamina

32
Q

where are perisinusoidal cells located and what do they do

A

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

33
Q

what happens to perisinusoidal cells during cirrhosis

A

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

34
Q

what does the sub endothelial space of disse contain

A

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

35
Q

what are characteristics of kupffer cells

A

phagocytic cell
derived from monocytes
lines hepatic sinusoids

36
Q

what does the bile canaliculus receive

A

bile from hepatocytes

37
Q

what does the canal of herring do

A

receives bile from canaliculus

carriers bile to bile ductule

38
Q

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

A

fibrinogen, prothrombin, factor VIII

39
Q

what do complement proteins do (ER in hepatocytes)

A

synthesized by hepatocytes, participate in destruction of pathogens

40
Q

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

A

the spiral valve of heister

41
Q

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

A

epithelium is tall columnar with a striated border

42
Q

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

A

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

43
Q

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

A

rotikansky-aschoff sinuses

44
Q

describe the serosa of the wall of the gall bladder

A

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

45
Q

what does the gallbladder release bile in response to

A

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

46
Q

define sphincter of oddi

A

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

47
Q

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

A

columnar epithelium with goblet cells

48
Q

where is alcohol oxidized to acetaldehyde (ethanol met)

A

in the cytoplasm

49
Q

where is acetaldehyde converted to acetate (ethanol met)

A

in mitochondria

50
Q

what is catalase

A

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

51
Q

what does TNF-alpha do during chronic liver diseases

A

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

52
Q

what is transforming growth factor beta secreted by

A

kupffer cells and hepatocytes

53
Q

what releases interleukin-6

A

kupffer cells

54
Q

what are the bile components

A

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

55
Q

what is the major pigment in bile

A

bilirubin

56
Q

where is conjugated bilirubin secreted into

A

intestine

57
Q

what is conjugated bilirubin in the intestine converted by and into

A

by bacterial action into urobilinogen

58
Q

where do bile salts emulsify dietary lipids

A

small intestine