Accessory Digestive Organs Flashcards
1
Q
Major functions of liver:
A
- Detoxification of metabolic waste (e.g., deamination of AA’s
➔ urea) - Metabolism & detoxification of drugs & toxins (e.g., alcohol,
antibiotics) - Destruction of senescent RBC’s
- Recycling of Hb via synthesis & secretion of bile
- Synthesis of plasma proteins (clotting factors, albumin,
lipoproteins) - Miscellaneous metabolic functions (fat, carbohydrate,
proteins, etc.)
2
Q
(Liver function) *Detoxification of metabolic waste (e.g., deamination of AA’s
➔ _____)
A
urea
3
Q
Products of digestion enter liver via ________
A
hepatic portal V
4
Q
hepatic portal V Also carries potentially toxic compounds absorbed from ___
to liver to be conjugated or detoxified
A
diet
5
Q
Oxygenated blood supplied to liver by _____, a branch of
celiac trunk ➔ R/L hepatic Aa in hepatic lobules
A
hepatic A
6
Q
Oxygenated blood supplied to liver by hepatic A, a branch of
celiac trunk ➔ ______ in hepatic lobules
A
R/L hepatic Aa
7
Q
R/L hepatic Aa – Carries only ~20-25% of blood to liver; mixes with
_____ blood from portal V to perfuse liver cells
A
unoxygenated blood
8
Q
Liver is a nutrient rich, but ____ poor environment
A
O2 poor
9
Q
Venous drainage of lobules via ____ ➔ hepatic V ➔
IVC
A
central Vv
10
Q
Venous drainage of lobules via central Vv ➔ hepatic V ➔
___
A
IVC
11
Q
Cell types found in liver:
A
hepatocytes, endothelial cells, kupffer cells, and stellate cells
12
Q
(cells in liver) – main functional cell, arranged in plates or cords
around sinusoids
A
Hepatocytes
13
Q
(cells in liver
– line the sinusoids
A
Endothelial cells
14
Q
(cells in liver)
* liver-specific macrophages
A
Kupffer cells –
15
Q
(cells in liver)
–storage of Vitamin A
A
- Stellate cells (Ito cells)
16
Q
Describe Hepatocytes
A
Polyhedral, round nucleus,
displaced chromatin &
prominent nucleolus
* Most hepatocytes diploid,
but some polyploid &/or
binucleate
* Contain large #’s of
cytoplasmic granules (rER
& lysosomal products) &
storage products
* Aging hepatocytes
accumulate brown
pigment, lipofuscin
17
Q
Hepatocytes–Contain large #’s of
______ (rER
& lysosomal products) &
storage products
A
cytoplasmic granules
18
Q
Aging hepatocytes
accumulate brown
pigment, _____
A
lipofuscin
19
Q
Individual hepatocytes
polygonal, arranged in
_______ paralleled
by venous sinusoids
A
anastomosing cords
20
Q
Individual hepatocytes
polygonal, arranged in
anastomosing cords paralleled
by ______
A
venous sinusoids
21
Q
Sinusoids lined by sinusoidal
lining cells, a _____
endothelium, with gaps
between endothelial cells
A
discontinuous
22
Q
Hepatic cords & sinusoids
supported by meshwork of
_____
A
reticulin fibers (Type III
collagen)
23
Q
Within sinusoids & space of
Disse are _______ cells
A
phagocytic Kupffer
cells (M)
24
Q
Occasional _____ cells
between hepatocytes—fat-
storing cells containing lipid
droplets, used for Vit A & D
storage
A
stellate or Ito cells
25
storing cells containing lipid
droplets, used for Vit A & D
storage
stellate or Ito cells
26
The liver has its own version of macrophage known
as the ______ .
Not only do these remove foreign particles,
they also work with the spleen to destroy old RBCs.
Kupffer cell
27
remove foreign particles,
they also work with the spleen to destroy old RBCs
Kupffer cell
28
major storage site
for vitamin A.
stellate cells
29
In liver injury, it becomes a
transitional cell or
myofibroblast-like cell capable
of synthesising collagen types I,
III and IV as well as laminin.
stellate cells
30
Thin, discontinuous, highly fenestrated
endothelium that does not rest on a
basement membrane
Hepatic sinusoids
31
Hepatic sinusoids separated from the hepatocytes by
the ___
space of Disse or the
perisinusoidal space
32
Found in the liver between a
hepatocyte and a sinusoid. It contains
the blood plasma.
Hepatic sinusoids
33
Microvilli of hepatocytes extend into
this space, allowing proteins and other
plasma components from
the sinusoids to :
be absorbed by the
hepatocytes.
34
Low resistance vascular channels that
allow blood to come into contact with
hepatocytes over a large surface area.
Hepatic sinusoids
35
Made by hepatocyte & secreted into bile canaliculi between cells
bile
36
Concepts of liver lobules:
Classical Hepatic Lobule
* Portal Lobule
* Hepatic Acinus of Rappaport
37
Cords of hepatocytes
arranged in _____
lobules
38
—based on
blood flow; roughly
hexagonal, with central V in
middle of lobule
Classic lobule
39
Classic lobule—based on
blood flow; roughly
hexagonal, with central V in
middle of lobule
(= centrilobular V, terminal
hepatic venule)
***
40
(hepatic lobule) Outer margin of each lobule
delimited by ___
thin, connective
tissue septum
41
____
located at each
“corner”, contain
hepatic A, br. portal
V, L, & bile duct
Portal tracts/ triads
42
(Portal tracts/triads)
Portal tracts/ triads
located at each
“corner”, contain
___
hepatic A, br. portal
V, L, & bile duct
43
(Portal tracts/triads)
Blood enters from
_____,
percolates through
sinusoids of lobule,
drains via central V
portal tracts
44
(Portal tracts/triads)
Blood enters from
portal tracts,
percolates through
sinusoids of lobule,
drains via ____
central V
45
____—triangular
area; based on bile flow
(opposite to blood flow)
--Portal triad in center &
central Vv at corners
Portal lobule
46
—diamond–shaped
region between neighboring
central Vv
Acinus
47
(Hepatic Ascini)
--Combines aspects of blood
flow, oxygenation, metabolism and pathology
--Acinus divided into zones 1,
2, & 3—
* Hepatocytes in different
zones have different
metabolic environments
***
48
(Hepatic Ascini)
—
closest to portal tract, receives most
oxygenated blood;
also most susceptible to toxic injury
Zone 1—(perilobular zone = periportal)
49
(Hepatic Ascini)
(intermediate zone)
zone w
50
(Hepatic Ascini)
—furthest
from portal tract, closest to central V
Receives least oxygenated blood; most
susceptible to ischemic injury
zone 3-(centrolobular zone)
51
Which Acinus zone is most susceptible to ischemic injury?
zone 3
52
Liver functions in detoxification or
metabolism of various drugs, toxins,
metabolites (e.g., ethanol, pesticides, &
carcinogens) via microsomal mixed function
oxidase system of ____
sER, or peroxidases of
peroxisomes (P450 system
53
A common sequela to repeated
insults or chronic disease is
____
cirrhosis
54
cirrhosis--Characterized by hepatic
degeneration & necrosis, followed
by fibrosis & nodular _____
regeneration
55
cirrhosis: Characterized by hepatic
____ & necrosis, followed
by fibrosis & nodular regeneration
degeneration
56
—associated
with cirrhosis (due to fibrosis,
blockage of blood flow)
Portal hypertension
57
T/F: Liver has ability to regenerate
True
58
Muscular sac located in depression
along surface of liver
* Used to store & concentrate bile;
volume ~100 ml
gallbladder
59
Gallbladder is lined by ______ epithelium with _____
simple columnar epithelium
with apical microvilli
60
Apical microvilli are used for:
resorption of water
61
T/F: Gallbladder has a thick muscularis mucosae
False--Gallbladder lacks a muscularis mucosae
62
(Gallbladder) Lamina propria highly folded with
____
occasional tubuloalveolar mucus
glands
63
____ stimulates
contraction of gallbladder
CCK (cholecystokinin)
64
Components of bile:
Water, ions, electrolytes, cholesterol +
phospholipids (= lecithin), bile acids (= bile salts) &
bile pigments
65
_____ is best known bile pigment—non-sol
breakdown product of Hb
Bilirubin
66
Pathology: Failure to absorb _____ or failure to
conjugate it & secrete => accumulation of bile
pigments & jaundice
bilirubin
67
Pathology: Failure to absorb bilirubin or failure to
conjugate it & secrete => accumulation of bile
pigments & ____
Jaundice
68
Supersaturation of bile => ____
gallstones (biliary
calculi, cholelithiasis)
69
(biliary
calculi, cholelithiasis)
gallstones
70
T/F: Gallstones are 1’ cholesterol & calcium salts
true
71
Obstruction of bile ducts (choledocolithiasis) =>
_____ if severe
bile stasis, or jaundice (icterus)
72
Obstruction of ____ =>
bile stasis, or jaundice (icterus) if severe
bile ducts (choledocolithiasis)
73
(choledocolithiasis)
bile ducts
74
(icterus)
jaundice
75
Chronic inflammation =>
cholecystitis
76
Sx removal of gallbladder is:
cholecystectomy
77
Following cholecystectomy, unable to concentrate ___; need to
limit ingestion of ____
bile; fats
78
Highly lobulated gland with
thin, connective tissue
capsule, located in bend of
duodenum
* Both exocrine & endocrine
components
pancrease
79
Ductless *endocrine*
pancreatic tissue located in
____
islets of Langerhans
80
Most of pancreas is
____ (i.e., with
ducts)—a compound,
acinar, serous gland
exocrine
81
Pancrease--Densely packed ___ contain pyramidal
secretory cells
surrounding a central
lumen (duct)
serous
acini
82
Acinar cells contain
____
(inactive enzyme
precursors)
zymogen granules
83
Acinar cells contain
zymogen granules
(inactive enzyme
precursors)—
e.g., trypsinogen (=
protrypsin),
chymotrypsinogen (=
prochymotrypsin),
amylase, lipase
review
84
Trypsin & chymotrypsin are
____; amylase breaks down
carbohydrates & lipases digest
lipids
proteases
85
Trypsin & chymotrypsin are
proteases; amylase breaks down
____ digest
lipids
carbohydrates & lipases
86
(exocrine pancrease) Empty into ______ (add
bicarbonate & water to pancreatic
sections; neutralize acidic chyme
from stomach => optimal pH for
pancreatic enzymes)
intercalated ducts
87
Duct cells that form beginning of
_____sometimes visible
in center of acini, called centro-
acinar cells
intercalated duct
88
Duct cells that form beginning of
intercalated duct sometimes visible
in center of acini, called ____
centro-
acinar cells
89
Intercalated ducts empty into
larger ______,
which exit into larger
interlobular (=extralobular)
ducts
*intra*lobular ducts
90
Intercalated ducts empty into
larger intralobular ducts,
which exit into larger
______ ducts
interlobular (=extralobular)
ducts
91
Pancreatic secretions enter
duodenum via _____ at major duodenal
papilla
pancreatic
duct
92
Pancreatic secretions enter
duodenum via pancreatic
duct at ____
major duodenal
papilla
93
Principle regulators of exocrine pancreas—
polypeptide hormones
secreted by enteroendocrine (APUD) cells
94
Principle regulators of exocrine pancreas— polypeptide hormones
secreted by _____
enteroendocrine (APUD) cells
95
polypeptide hormones secreted by stomach
gastrin
96
secreted by “G” cells of pyloric stomach; stimulates secretion of
pancreatic fluid
gastrin
97
polypeptide hormones secreted by duodenum (3)
secretin, CKK, enterokinase
98
secreted by “S” cells; stimulates secretion of bicarbonate by cells of
intercalated ducts
secretin
99
secreted by “I” cells, stimulates acinar
cells to secrete zymogens
CCK (cholecystokinin = pancreozymin)
100
—converts trypsinogen ➔ trypsin (within small intestine), which
converts chymotrypsinogen ➔ chymotrypsin (digests proteins)
Cascade rxn prevents pancreas from digesting itself
enterokinase
101
—autodigestion
of pancreas brought on by
alcoholism
Pancreatitis
102
(Pancreatitis)
Cascade rxn breaks down =>
Premature conversion of
chymotrypsinogen to
______ & autolysis
chymotrypsin
103
Pancreatitis—autodigestion
of pancreas brought on by
____
alcoholism
104
Kupffer cells work with the ______ to destroy old RBCs.
spleen
