GI- liver and pancrease Flashcards
(97 cards)
1
Q
lobes of the liver
A
right, left, caudate, quadrate
2
Q
ligamentum teres
A
remnant of umbilical vein nestled within the falciform ligament
3
Q
what is the function of hepatic ducts?
A
to bring bile and bile salts from the diff. parts of the liver
4
Q
where do bile/bile salts go in-between meals?
A
they go up through the cystic duct to be stored in the gallbladder
5
Q
gallstones
A
aggregations of cholesterol salts that can block the cystic duct opening and create pressure within the gallbladder (may req. surgical removal)
6
Q
where is the pancreas located?
A
it is nestled within the curvature of the duodenum
7
Q
pancreatic duct
A
conducts pancreatic juice from the pancreas to the small intestine; another duct combines w/ common bile duct to receive secretions from pancreas + liver and gallbladder
8
Q
porta hepatis
A
central area of the liver where the portal vein, common duct, and hepatic artery enter
9
Q
common hepatic duct
A
large bile duct leading from liver; brings bile salt being secreted by the liver out
10
Q
Sphincter of Oddi
A
the valve controlling release of bile and pancreatic juice into the small intestine; it is closed in-between meals
11
Q
dual blood supply of liver
A
- liver receives oxygen-rich blood from the abdominal aorta via the celiac trunk
- mixes w/ deoxygenated nutrient rich blood from GI via hepatic portal vein
- blood is then drained by the haptic vein to travel to the IVC
12
Q
hepatocytes
A
most predominant cell type in liver
13
Q
Kupffer cells Responsibility
A
- phagocytosis of microbes
- cytokine production
- recycle heme
14
Q
liver lobule
A
basic functional unit of the liver
- six-sided structure
15
Q
portal triad of liver
A
- bile duct receiving bile from canaliculi
- portal venule from hepatic portal vein
- hepatic/portal arteriole
16
Q
central vein
A
drains blood from sinusoids and out of liver (becomes hepatic vein)
17
Q
what are the roles of the liver?
A
- process and/or store intestinal nutrients (carbohydrates, amino acids, lipids & vitamins)
- synthesis of serum proteins
- process drugs and hormones
- storage of iron & excretion of bilirubin
- deals with microbes (Kupffer cells)
- aids in digestion (bile)
18
Q
processing of carbohydrates
A
- the liver stores glucose as glycogen to provide 1-2 days/ supply of gluco
- glucose can be converted into FAs or triglycerides,
- galactose and fructose can be converted to glucose, gluconeogenesis and glycogenolysis
19
Q
gluconeogenesis
A
formation of glucose from noncarbohydrate sources e.g. lactic acid, pyruvate, amino acids, glycerol
20
Q
processing of amino acids
A
essential a.a.’s are used for protein synthesis (serum proteins)
21
Q
processing of lipids
A
the liver packages fats into forms that can be transported to/from tissues
22
Q
VLDL
A
transports fats made by hepatocytes to adipocytes
23
Q
LDL
A
transports dietary/synthesized cholesterol to tissues
24
Q
HDL
A
returns excess cholesterol from tissues to liver (catabolized & secreted in bile salts)
25
synthesis of serum proteins
the liver synthesizes most plasma proteins such as albumin (60%), coagulation factors, complement proteins, and alpha and beta globulins (angiotensinogen and transferrin)
26
albumin
- protein in blood
27
process drugs and hormones
- most drugs pass through the liver
- excreted in bile, inactivated or converted into a form the kidneys can also excrete
- can also alter/excrete thyroid & steroid hormones
28
ferritin
- iron storage protein
| - storing 10% of iron in the liver
29
transferrin
iron transport protein
30
what happens to heme from damaged RBCs?
it is returned to the liver where iron is scavenged and the heme is discarded as bilirubin
31
bilirubin
pigment released by the liver in bile
32
jaundice
accumulation of bilirubin in tissues
33
how does the liver aid in digestion of fats?
by producing bile
34
what is bile essential for?
- lipid digestion + absorption
- cholesterol metabolism
- excretion of lipid-soluble drugs
35
what is bile composed of?
bile acids (salts) - emulsification, cholesterol, bilirubin and electrolytes
36
gallbladder
thin green sack w/ muscular wall that concentrates and stores bile until needed
37
in which way is gallbladder function controlled?
neurally and hormonally
38
PNS control of gallbladder
weak contractions
39
CCK control of gallbladder
intense contractions (release of stored bile)
40
secretin control of gallbladder
increased prod. of bicarbonate-rich bile by liver hepatocytes
41
pancreas composition
primary exocrine gland but has clusters of endocrine cells
42
exocrine products of pancreas
pancreatic enzymes that enter the duodenum via the hepatopancreatic ampulla (90%)
43
endocrine products of pancreas
insulin and glucagon which enter the bloodstream
44
how is exocrine function of the pancreas regulated?
neural and hormonal:
1. vagal nerve stim. causes release of pancreatic juice during cephalic + gastric phase
2. chyme entering duodenum causes enteroendocrine cells to release secretin & CCK which enters bloodstream
4. upon reaching the pancreas CCK induces enzyme secretion, secretin induces secretion of bicarb-rich juice
45
pancreatic endocrine function
blood glucose homeostasis
46
how does the pancreas fix high blood sugar?
promotes insulin release therefore stimulating formation of glycogen from glucose in the liver to lower blood sugar
47
how does the pancreas fix low blood sugar?
promotes glucagon release therefore stimulating glycogen breakdown to glucose in the liver to raise blood sugar
48
Caudate Lobe
towards the tail
49
Quadrate lobe
square shaped
50
How are the exposed lobes of the liver separated
falciform ligament
51
What structure is inferior to the liver
gallbladder
52
function of gallbladder
tiny muscular sac that stores bile
53
What structure makes bile
liver hepatocytes make bile to emulsify fats; stored in gallbladder until needed
54
Where is the pancreas located
tucked into the curvature of the duodenum
55
Pancreas responsibility
secreting pancreatic enzymes and bicarb rich mucous to neutralize acid chyme from stomach
56
Where do the products from the liver, gallbladder and pancreas end up?
hepatopancreatic ampulla
57
Porta Hepatis
door to the liver
58
Hepatic portal vein
delivering nutrient rich but oxygen poor blood to liver
59
Hepatic artery
delivering oxygen rich blood to liver
60
Is there mixed blood in the liver and why?
Yes; hepatic portal vein and artery
61
What occurs during meal time?
sphincter opens up to the duodenum and bile flows from the liver and gallbladder
62
Primary blood supply coming into the liver is from?
hepatic portal vein; can be oxygen poor because intestines have taken some already
63
Where does the mix with arterial blood come from?
celiac trunk
64
Hepatocytes responsibility
responsible for synthesis, storage, detoxification and metabolism
65
How are endocrine hormones cleared out of circulation?
by the liver
66
Kupffer cells
aid in inflammation and help break down red blood cells to recycle
67
Sinusoidal Endothelial cells
- have huge gaps between them
- formed by sinusoidal capillaries
- albumin and all the clotting factors and compliment proteins made by liver need to go into circulation by sinusoids
68
At each of the 6 corners there is duct work that contains
artery, vein and bile duct
69
Where do portal vein blood and hepatic arterial blood come into the liver from...
liver lobule from periphery and drain into the centre
70
What do hepatocytes do?
pull up digested nutrients
71
What do macrophages do?
look for pathogens
72
Bile Canalicular
exists between hepatocytes of the liver creating the bile and sending it to the edges of the lobules collected by the bile ducts
73
Glucose can be converted to
- into FAs or triglycerides,
74
What can be converted into glucose?
galactose and fructose can be converted to glucose, gluconeogenesis and glycogenolysis
75
Glycogenolysis
breaks up glyocogen (1-2 days worth) into glucose
76
How does skeletal muscle store glucose?
for itself; phosphorylated and cannot pass plasma membrane to share
77
How is ammonia produced?
during the breakdown of amino acids in the liver for energy purposes
78
Ammonia is converted to
The liver can convert ammonia to urea
79
Is urea water soluble?
yes so the kidneys can get it out
80
Cholesterol generation
mostly from liver itself and some from dietary
81
Fibre is needed to
trap cholesterol
82
Vitamin A (fat soluble vitamins)
A - converted to retinyl esters for vision (rods
83
Vitamin D (fat soluble vitamins)
D - utilized in bone metabolism (calcium absorption)
84
Vitamin E (fat soluble vitamins)
E - antioxidant (free radical scavenger)
85
Vitamin K (fat soluble vitamins)
K - utilized by hepatocytes to form coag. factors)
86
albumin functions
- maintains the proper amount of water in the blood via colloid osmotic pressure
- binds hormones, cations, bilirubin, drugs, etc.
- any lipid soluble hormone will use albumin to transport
87
Does albumin ever cross the capillary bed?
No it will draw it back with oncotic pressure
88
Coagulation factors
- made in the liver
| - every singe component of coagulation cascade comes from hepatocytes
89
Compliment proteins
involved in the inflammatory response
| - come from hepatocytes
90
Globulins
- come from hepatocytes
- alpha globulins (antitrypsin)
- beta globulins (angiotensinogen and thyroxine binding globulin)
91
Where is most of the bodies iron located?
on hemoglobin in RBC
92
Jaundice occurs
hepatocytes are scarred or damaged (hepatisis or drugs)
93
Where do most macrophages reside
in the liver
94
Natrual killer cells
innate immune cells responsible for killing virus infected host cells
95
Why is bile released?
in response to parasympathetic stimulation and CCK
96
how do exocrine products pancreatic enzymes and bile enter the duodenum through?
the hepatopancreatic ampulla
97
Exocrine function
make digestive enzymes
