week 7 Flashcards
what are the Accessory Organs of Digestion
- liver
- Gallbladder
- Pancreas
function of liver
– Many functions but only digestive function is bile production
* Bile - detergent-like fat emulsifier
Gallbladder function
Concentrates and
stores bil
Pancreas function
– exocrine function:
produces pancreatic
juice
– endocrine function:
produces hormones
that control bloodglucose levels
label this diagram
where is Liver located?
Located below
diaphragm in upper
right abdomen
what is liver composed of?
Liver is composed
of four lobes: right
and left (separated
by the falciform
ligament), caudate
and quadrate
(back)
what does falciform ligament do
Falciform ligament
suspends the liver
from the diaphragm
label this diagram
label this diagram
what is glycogenesis,
Turning glucose into
glycogen (for storage)
what is glycogenolysis
Turning glycogen
into glucose (for fuel)
what is gluconeogenesis
Creating glucose from
non-carbs (for fuel)
functions of the liver
Carbohydrate metabolism (maintenance of blood glucose
level: glycogenesis, glycogenolysis, gluconeogenesis)
* Lipid metabolism(synthesis of lipoproteins and cholesterol)
* Protein metabolism (conversion of one amino acid into
another, synthesis of plasma proteins such as albumin and
blood clotting factors)
* Processing of drugs and hormones (detoxifying)
* Processing and excretion of bilirubin (breakdown product
of haemoglobin) into bile
* Synthesis of bile acids (needed for digestion of lipids)
* Storage (glycogen, iron, vitamins A, B12, D, E, K)
* Phagocytosis (via Kupffer cells)
* Activation of vitamin D taken in food (together with
kidneys)
what are the Microscopic Anatomical features of the liver
liver lobules and portal triad
what are liver lobules
– Hexagonal structural and functional units
what are liver lobules composed of
– Composed of plates of hepatocytes (liver cells)
function of plates of hepatocytes (liver cells)
- Filter and process nutrient-rich blood
- intertwined with sinusoidal capillaries and
bile canaliculi
where is Central vein in longitudinal axis found
in liver lobules
where are portal triads found?
at each corner of liver lobule
portal triad contains…..
– Branch of hepatic artery
– Branch of hepatic portal vein brings nutrient-rich blood
– Bile duct receives bile from bile canaliculi
Branch of hepatic artery function
brings oxygen-rich blood
Branch of hepatic portal vein function
sends nutrient-rich blood from the gastrointestinal tract and spleen to the liver, but also delivers toxins to the liver
Bile duct function
receives bile from bile canaliculi
Liver receives blood from:
- hepatic portal vein
bringing nutrient-rich blood
from stomach/spleen and
intestines - hepatic artery bringing
oxygen-rich blood
liver blood flow
Blood from both …. …..
and …… ……. mixes in
…….. ………. capillaries
(liver sinusoids) and flows
towards the …….. vein in the
centre of the …….. ……….
Blood from both portal vein
and hepatic arteries mixes in
liver sinusoidal capillaries
(liver sinusoids) and flows
towards the central vein in the
centre of the liver lobule
blood flow in liver #2
…….. …….. join to form a
……. ……. ……. –> goes to
…….. –> …….. ………
Central veins join to form a
single hepatic vein —> goes to
IVC —> right atrium
Bloodflow in liver flowchart
Gall Bladder shape
pear shaped sac
Gall bladder location
located underneath right lobe
of liver
Gall bladder function
stores and concentrates bile
Bile flow from liver to gallbladder?
– bile from liver –>
right and left hepatic ducts –>
common hepatic duct –> cystic duct
Bile flow from gallbladder to
duodenum
– bile in gallbladder –> cystic duct
–> common bile duct –>
hepatopancreatic ampulla –>
duodenum
label this gallbladder diagram
how much Bile is produced by liver per day?
800 -1,000 mL/day is produced by the liver
ph of bile
- pH is 7.6-8.6 (alkaline)
what is the composition of bile?
Composition: water, ions, bile acids, cholesterol, lecithin
(phospholipid), bile pigments (conjugated bilirubin)
function of bile
emulsification of large lipid globules by bile
acids and lecithin (mechanical digestion) breaking them down into small globules to increase the surface for action of lipase enzymes (chemical digestion).
chemical composition of bile diagram
what gives faeces its brown colour
In the large intestine, bilirubin (from bile) is
converted into stercobilin which gives faeces
its brown colour
how much bile acid is reabsorbed? where do they go
80% of bile acids are reabsorbed in the
terminal ileum; they go back to the liver via the
portal vein and are re-excreted into the bile
(enterohepatic circulation)
how much bile acid is excreted and where does it go?
20% of the bile acids are excreted in the faeces
and this is the body’s only way of eliminating
excess cholesterol (liver synthesises new bile acids
from cholesterol to replace those lost in faeces)
what is the Pancreas
Mostly retroperitoneal organ, deep to the greater curvature of the
stomach
what are the main parts of the pancreas
Main parts: head, body and tail
pancreas function
the exocrince and endocrine parts of the pancreas both produce things.
what does Exocrine pancreas produce
glandular cells produce 1.2-1.5 L/day of digestive
pancreatic juice
Pancreatic juice is drained into the……..
Pancreatic juice is drained into the duodenum via the main pancreatic
duct and to some extent, the accessory duct
Pancreatic …… joins common ….. duct that comes from the ……
forming …… ……. that joins …….
Pancreatic duct joins common bile duct that comes from the liver
forming hepatopancreatic ampulla that joins duodenum
what does endocrine pancreas produce
pancreatic
islets contain cells that
produce hormones
glucagon and insulin (that
control blood glucose
level) which are released
into the bloodstream
label this diagram of pancreas
what is Pancreatic Juice composed of?
– water, salts and bicarbonate (hydrocarbonate) ions and digestive enzymes
how is pancreatic juice alkaline?
neutralises acidic gastric
juice in chyme, stops the action of pepsin; creates the
proper pH for pancreatic and intestinal digestive enzymes
(they would not work in acidic environment)
examples of digestive enzymes and their functions
- pancreatic amylase –> carbohydrate starch breakdown
- trypsin, chymotrypsin and procarboxypeptidase –> protein breakdown
- pancreatic lipase –> most of triglyceride breakdown
- deoxyribonuclease and ribonuclease –> nucleic acids breakdown
steps of Release and Secretion of
Pancreatic Juice and Bile
specific organs are specialised for ………….
specific organs are specialised for digesting
different food types to provide nutrients
what is nutrient?
- nutrient = food substance that promotes normal
growth maintenance or repair of the body.
– carbohydrates, fats, proteins, minerals, vitamins
and water (45-50 essential nutrients from diet)
specific enzymes ………
specific enzymes catalyse reactions to digest
food molecules to their basic building blocks
examples of specific enzymes
– carbohydrates –> simple sugars
– proteins –> amino acids
– fats –> fatty acids, glycerol and monoglycerides
what is Hydrolysis?
Water is added to nutrient molecules as they are
broken down by enzymes
Each hydrolysis reaction requires a …….
specific enzyme
Body uses …..L of water a day
Body uses 7-9L of water a day
role of water in digestion
Not only used in production of digestive juices and
food dilution but is also involved in the chemical
process itself
what are the 2 types of Neural Control of Digestion
Sympathetic (fight
or flight) and Parasympathetic
(rest and digest)
what happens in Sympathetic (fight
or flight) digestion
GIT: decreases
secretion and motility,
increases sphincter
closure
what happens in Parasympathetic
(rest and digest) digestion
GIT: increases
secretion and motility,
decreases sphincter
closure
diagram of neural controls of digestion
diagram of enzymes in digestion
how are carbohydrates chemically digested in the mouth and duodenum?
- salivary and pancreatic amylase break down starch
into maltose, maltotriose (disacchaarides and
trisaccharides) and α-dextrins (oligosaccharides)
how are carbohydrates chemically digested in the small intestine?
- intestinal lining brush-border enzymes; α-dextrinase,
sucrase, lactase and maltase digest the
oligosaccharides, trisaccharides and disaccharides into
monosaccharides
Chemical digestion of carbohydrates diagram
Chemical digestion of proteins in stomach
HCl denatures and unfolds proteins preparing them for
easier chemical digestion, pepsin breaks proteins into
small peptides
Chemical digestion of proteins in Duodenum
pancreatic enzymes; trypsin, chymotrypsin and
carboxypeptidase continue breaking proteins into
small peptides
Chemical digestion of proteins in small intestine
various peptidase enzymes in intestinal lining brush
border finish digestion of peptides into amino acids
Chemical digestion of proteins diagram
Mechanical and Chemical digestion of lipids in Duodenum
- emulsification by bile (physical/mechanical breakdown
into smaller droplets) - pancreatic lipase (chemical digestion) splits lipids into
fatty acids and monoglycerides (glycerol + 1 fatty acid)
Chemical digestion of nucleic acids in Duodenum
- pancreatic ribonuclease digests RNA,
deoxyribonuclease digests DNA into nucleotides
Chemical digestion of nucleic acids in small intestine
- brush-border enzymes break down nucleotides into nitrogenous bases, pentose sugars and phosphates
Mechanical and Chemical digestion of lipids diagram
Chemical digestion of nucleic acids
how is Absorption in the Small Intestine achieved
Absorption can be achieved via simple diffusion,
facilitated diffusion, active transport and osmosis
(water) – across simple columnar epithelium
What is normally absorbed in the Small Intestine?
- What is normally absorbed:
– monosaccharides
– amino acids
– monoglycerides, fatty acids (after absorption inside epithelial
cells triglicerides are rebuilt and coated with protein to form
chylomicrons which are passed into lymph)
– electrolytes
– vitamins (vitamin B12 requires intrinsic factor for its
absorption)
– water
what are the steps of Absorption in the Small Intestine
- Large fat globules are emulsified
(physically/mechanically broken up into smaller
fat droplets) by bile salts in the duodenum.
-Digestion of fat by the pancreatic enzyme,
lipase, yields free fatty acids and
monoglycerides. These then associate with bile
salts to form micelles which “ferry” them to the
intestinal mucosa.
- Fatty acids and monoglycerides leaves micelles
and diffuse in to epithelial cells. There they are
recombined and packaged with other lipid
substances and proteins to form chylomicrons. - Chylomicrons are extruded from the epithelial
cells by exocytosis. The chylomicrons enter
lymphatic lacteals. They are carried away from
the intestine by lymph.
Absorption in the Small Intestine diagram
why do lipids need protein carriers?
- Lipids are hydrophobic (water insoluble) so they need
protein carriers for transport in blood
what are lipoproteins
complexes of lipids and proteins in blood are called lipoproteins
example of lipoproteins
- chylomicrons
- very low-density lipoproteins (VLDL)
- low-density lipoproteins (LDL)
– high-density lipoproteins (HDL)
function of chylomicrons
used for transport of dietary lipids to
adipose tissue
very low-density lipoproteins (VLDL) function
made in liver to
transport triglycerides to all tissues; converted to LDLs after
removal of some triglycerides
low-density lipoproteins (LDL) function
remnants of VLDL; carry
cholesterol to cells; after they give away cholesterol they are
repackaged into VLDL in the liver; as they are rich in
cholesterol they are often called “bad lipoproteins”
high-density lipoproteins (HDL) function
remove excess
cholesterol from peripheral tissues and transport to liver for
disposal (“good lipoproteins”)
diagram of lipoproteins
Sources of cholesterol for the body=
Sources of cholesterol for the body are food (eggs,
dairy, meat) and synthesis in the liver (from
acetyl-CoA)
reasons for elevated cholesterol
Elevated cholesterol in blood can be genetic but the
most common cause of is too much saturated fats
in food, not too much cholesterol in diet
how can Good lipid profile in blood be accomplished
Good lipid profile in blood can be accomplished by
regular exercise, diet (watch cholesterol intake but
also saturated fats), avoiding smoking and
cholesterol-lowering medications (if needed)
when does Absorptive state occur?
Absorptive state occurs after a meal when nutrients
are entering the bloodstream (lasts around 4 hours
per meal)
what are the Events during Absorptive State
- Glucose from carbohydrates is readily available for ATP
production (about 50% of absorbed glucose)
− The rest of glucose is converted to glycogen (10%) and
triglycerides (40%)
− Dietary lipids are stored in adipose tissue
− Amino acids enter Krebs cycle or are converted to fatty
acids
− Amino acids which are not taken up by hepatocytes are
used by other cells for synthesis of their proteins
− The main regulating hormone is insulin: increases uptake
of glucose and synthesis of glycogen, proteins and
triglycerides
Events during Post-Absorptive State
- Absorption of nutrients from GI tract is complete and
body must meet its needs without outside nutrients - Maintaining normal blood glucose level is a major
challenge; glucose enters blood from 2 major sources
– glycogen breakdown in liver (usually sufficient till next meal)
– gluconeogenesis using amino acids and glycerol - Most body tissues switch to using fatty acids (from
adipose tissue) for energy production
– The only exceptions are brain and kidneys which must use
glucose for their energy metabolism
what are the main regulating hormone in Events during Post-Absorptive State?
- Main regulating hormones: glucagon (glycogenolysis),
adrenaline (glycogenolysis and lipolysis) and cortisol
(gluconeogenesis)
what is the main regulating hormone in events during absorptive state
The main regulating hormone is insulin: increases uptake
of glucose and synthesis of glycogen, proteins and
triglycerides
what are the parts of Large Intestine
Parts: caecum, ascending colon, transverse colon,
descending colon, sigmoid colon, rectum and anus
colon positioning in large intestine
Ascending colon and descending colon are
retroperitoneal (behind the peritoneum)
* Transverse colon and sigmoid colon are anchored via
mesocolons (transverse and sigmoid mesocolon)
Unique features of large intestine
Unique features:
– teniae coli – three bands of longitudinal
smooth muscle in the wall
– haustrae – pocket like sacs caused by the
contractions of the teniae coli
– epiploic appendages – fat-filled pouches
of visceral peritoneum
location of anal canal
Anal canal = last 2-3 cm of GI tract
anatomy of large intestine diagram
Mucosa of large intestine contains…
- Mucosa of large intestine has no villi (only microvilli),
absorptive cells and goblet cells (produce mucus)
what are the processes in the large intestine
mechanical digestion and chemical processes and absorption or water etc
what is mechanical digestion in the large intestine?
Mechanical digestion – slow peristaltic waves for
churning and mixing of the content
what are the Chemical processes in the large intestine?
Chemical processes – bacterial fermentation of
undigested carbohydrates (into carbon dioxide and
methane gas), undigested proteins (into simpler
substances such as indoles -odour) and bilirubin from
bile into other pigments (stercobilin gives stool its colour)
why is water absorbed in the large intestine
Absorption of water and some electrolytes forms solid
faeces (largely contains undigested materials such as
cellulose, but also numerous bacteria)
how much fluid deposited into GI tract each day
Around 9 litres of fluid is
deposited into GI tract
each day from various
organs and ingestion
how much fluid does small intestine reabsorb
Small intestine reabsorbs:
~8L
how much fluid does large intestine reabsorb
- Large intestine reabsorbs:
~900mL
what process is water absorbed through in GI tract?
Absorption is by osmosis
through cell walls into
vascular capillaries inside
villi (SI) / microvilli (LI)
diagram of absorption of water
what is Defaecation?
Colonic peristaltic activity slowly moves faeces into rectum
what is the process of defaecation?
- When full, rectal stretch receptors signal parasympathetic
centres in sacral spinal cord - Parasympathetic nerves contract muscles of rectum and
relax internal anal sphincter (smooth muscle) - External anal
sphincter skeletal
muscle) is voluntarily
controlled –
defaecation can be
postponed for some
time
diagram of defaecation
what does too slow/inadequate secretions mean
insufficient nutrition
what does too fast/excess secretions mean?
incomplete
digestion/absorption and mucosal damage
what are Two types of controls of eating
– hormonal influences from the gut
– neural influences from the autonomic nervous system and
hypothalamus
difference between Hunger and Appetite
– Hunger: desire for food in response to blood nutrient levels
* regulated by the hypothalamus
– Appetite: desire for food but is not related to the need for food
* influenced by hormones, emotional state, habits, etc.
what is a Short-term regulation of food intake
– hormones
* stimulate hunger
* depress hunger
* produce eating and food seeking behaviours
what is a Long-term regulation of food intake
– Leptin “energy expenditure hormone”
* hormone secreted by fat cells in response to increased body fat
mass
* protects against weight loss in times of nutritional deprivation
* acts of hypothalamus
– supresses potent appetite stimulant
– stimulates the expression of appetite suppressants
On which organ would
you find the falciform
ligament?
the liver
Which cells secrete
cholecystokinin and
secretin? Where would
you find these cells?
Enteroendocrine cells
Duodenum
Identify structures
labelled A – D
A. Cystic duct
B. Major pancreatic duct
C. Common Bile duct
D. Body of pancreas
What type of chemical
digestion occurs in the
large intestine?
Bacterial Fermentation
What type of mechanical
digestion occurs in the
large intestine?
Peristalsis
The pancreas is located
superior to the stomach
(TRUE/FALSE)
FALSE
What is mechanical digestion?
The physical breakdown of foodstuffs.
Where does mechanical digestion occur and which organs or processes play a role in this type of digestion?
- Mouth: Teeth and Tongue
- Stomach: Stomach walls (grind
and churn foodstuffs) - Duodenum (small intestine): Bile
from Gallbladder - Jejunum and Ileum (small
intestine): intestinal walls
(segmentation) - Large Intestine: intestinal walls
(slow peristaltic waves)
What is chemical digestion?
The chemical breakdown of
foodstuffs, with enzymes and
acids
Where does chemical digestion occur and which
organs or processes play a role in this
type of digestion?
- Mouth: Digestive enzymes
produced in salivary glands (ask
students to name the 3 salivary
glands) - Stomach: Digestive enzymes
produced by gastric mucosa, acids
produced by gastric mucosa - Duodenum (small intestine):
Digestive enzymes from pancreas - Jejunum and Ileum (small
intestine): Digestive enzymes
produced by the intestinal brush
border (ask them to describe the
brush border) - Large Intestine: bacterial fermentation
What is the ultimate goal of mechanical and chemical digestion?
To break down large foodstuffs to their smallest building blocks, so that the body
can absorb them.
What is the vital molecule required for optimal mechanical and chemical digestion? How
much does the body use per day for digestion? And does the body reabsorb this molecule
at any stage?
Water. 7-9 L per day. Yes, it reabsorbs absorbs around 98% (mostly in
the small intestine)
what are the Basic Building Blocks of Carbohydrates?
Simple sugars such as Galactose, Glucose and Fructose
what are the Basic Building Blocks of proteins?
Amino acids, some dipeptides and tripeptides
what are the Basic Building Blocks of lipids?
Monoglycerides, triglycerides and fatty acids
what are the Basic Building Blocks of nucleic acids?
Pentose sugars, Nitrogenous bases and
phosphate ions
Absorption in the small intestine can be achieved by:
Simple diffusion,
Facilitated diffusion, Active Transport and Osmosis.
In the intestines, do all nutrients get absorbed into the blood?
No, most fatty acids are absorbed into lacteals, which are lymph vessels.
What are lipoproteins? What are some examples of Lipoproteins and their
function?
Lipids are hydrophobic (water insoluble) so they need protein carriers for
transport in blood; complexes of lipids and proteins in blood are called
lipoproteins: Here are some examples of lipoproteins.
* chylomicrons – used for transport of dietary lipids to adipose tissue
* very low-density lipoproteins (VLDL) – made in liver to transport
triglycerides to all tissues; converted to LDLs after removal of some
triglycerides
* low-density lipoproteins (LDL) – remnants of VLDL; carry cholesterol to
cells; after they give away cholesterol they are repackaged into VLDL in the
liver; as they are rich in cholesterol they are often called “bad lipoproteins”
* high-density lipoproteins (HDL) – remove excess cholesterol from
peripheral tissues and transport to liver for disposal (“good lipoproteins”)
Where does the nutrient-rich blood from the intestines eventually lead to?
It eventually leads to the liver, via the portal vein.
Label this diagram
LABEL THIS
) What is a portal triad? Where are they located?
Bile duct, portal venule, portal
arteriole. At each corner of the liver lobules.
Which vessels bring deoxygenated, nutrient rich-blood to the liver lobule? Where
did this blood come from?
Portal venules. This blood has come from the portal
vein (blood from gut).
Which vessels bring oxygenated, nutrient-poor blood to the liver lobule? Where did
this blood come from?
Portal arterioles. This blood has come from the hepatic
arteries which come from the celiac trunk, from the abdominal aorta.
Which vessels do bile salts and bicarbonate drain into? Where do they eventually
lead?
? Bile ducts, eventually lead into the gallbladder.
What are the liver cells that absorb nutrients called?
Hepatocytes
How is the deoxygenated, nutrient-rich blood delivered to these cells?
Via liver
sinusoids (remember sinusoids are extremely leaky capillaries)
) Once the liver cells absorb the nutrients, where does the deoxygenated, nutrientpoor blood drain? Where does this blood go?
? This blood drains into the central
vein, which eventually leads back into the IVC via hepatic veins.
What is the function of the gall bladder?
Store and concentrate bile
What is bile? What is its function?
water, ions, bile acids, cholesterol, lecithin (phospholipid), bile pigments (conjugated
bilirubin)
c) Is bile involved in mechanical or chemical digestion?
Mechanical – by physically separating larger fat globules into small fat globules.
d) What would be the result if the opening of the gall bladder was blocked?
no bile emulsifying fats in duodenum, makes it more difficult for lipases to break fats
down further for reabsorption fatty diarrhoea
Can an individual survive without a gall bladder?
Yes, they may have to have a reduced fat diet and take oral lipase tablets to assist
with fat digestion.
) What is the pancreas’ exocrine function?
To make pancreatic juice with digestive enzymes
What is pancreatic juice? What are the important constituents of pancreatic juice?
water, salts and bicarbonate (hydrocarbonate) ions
pancreatic juice is alkaline neutralises acidic gastric juice in chyme, stops the action of pepsin;
creates the proper pH for pancreatic and intestinal digestive enzymes (they would not work in acidic
environment)
digestive enzymes
pancreatic amylase carbohydrate starch breakdown
trypsin, chymotrypsin and procarboxypeptidase protein breakdown
pancreatic lipase most of triglyceride breakdown
deoxyribonuclease and ribonuclease nucleic acids breakdown
What is the pancreas’ endocrine function?
pancreatic islets contain cells that produce hormones
) Specifically what does the pancreas release into the bloodstream?
glucagon and insulin (that control blood glucose level) which are released into the
bloodstream
What is the primary
movement type in the large
intestine?
Peristalsis
Which anal sphincter is
voluntary?
External
true/false. Chylomicrons, very low-density lipoproteins, low-density lipoproteins and high-density lipoproteins are involved in transporting hydrophilic (water insoluble) lipids around the body.
false
The main regulating hormones that are involved in the post-absorptive state are:
the main regulating hormones during the post-absorptive state: glucagon (for glycogenolysis), adrenaline (for glycogenolysis and lipolysis) and cortisol (for gluconeogenesis).
What substances from different organs would mix together at the Hepatopancreatic ampulla?
bile and pancreatic enzymes
In the GIT, the majority of water reabsorption occurs in the:
small intestine
The final product of carbohydrate digestion is __________.
monosaccharides
In the gastrointestinal tract, the parasympathetic nervous system______________.
decreases gluconeogenesis, increases tone and mobility, and decreases sphincter closure
Which of the following is a characteristic of the large intestine?
a.
It contains a large number of bacteria.
b.
It has villi.
c.
It is the site for acid neutralisation.
d.
It provides no absorptive function.
e.
It is longer than the small intestine.
You are incorrect.
The large intestine contains a large amount of bacteria which functions to further breakdown digested material
In order to prevent self-digestion of the pancreas, activation of pancreatic proteases occurs in the __________.
duodenum
true/false. The sympathetic nervous system decreases tone, secretion and motility, and increases sphincter closure in the GIT.
True
a. common hepatic duct
b. cystic duct
c. main pancreatic duct
d. head of pancreas
e. Ampulla of Vater/Hepatopancreatic ampulla
a. transverse colon
b. ascending colon
c. caecum
d. descending colon
e. sigmoid colon
a. right lobe of liver
b. ascending colon
c. caecum
d. appendix
e. descending colon
f. rectum
What are the main tribituraries of the portal vein?
The Superior mesenteric vein, Inferior mesenteric vein and the Splenic vein are the main tributaries of the portal vein.
The portal vein receives the oxygen poor, nutrient rich blood from the digestive tract and transports it to the liver.
a. inferior vena cava
b. left lobe of liver
c. falciform ligament
d. right lobe of liver
e. caudate lobe
f. hepatic vein
g. cystic duct
h. right hepatic duct
i. gall bladder
This vessel supplies oxygenated blood to many structures, including; the liver, stomach and spleen.
Celiac Trunk
Which artery supplies the jejunum, ileum and the ascending colon? Where does this artery arise from?
.
Superior Mesenteric Artery from the Abdominal Aorta
What is the functional unit of the liver?
A liver lobule
