Digestive System (2)
The accessory organs are the liver – the gallbladder – the pancreas:
1-Food does not pass through them
2-Produce some materials to help in food digestion
→ It has the shape of a banana / feather
- Located behind the stomach → Remove the stomach in order to see it.
- Has a wide and a narrow end. This long end is found along with long duodenum “Which
comes from the stomach”
-Has 3 parts (Head-Body-Tail) [spleen is at the tail]
- It is a gland that secretes solution called pancreatic juice → help in digestion of food.
It goes from all part of the pancreas to one main duct.
-Accessory duct: additional one “not everyone has it”
Pencreatic duct and bile duct called “Hepatopancreatic ampulla”
- Hepatopancreatic ampulla opens in an opening in the duodenal papilla - where all the
juices from the pancreas along with many things mix together and go to the duodenum to
help in the digestion of food.
Exacrine glands or
"secretion goes to the
duct then the blood"
Helps in digestion
-Produces pencreatic juice (for
digestion), it will go through
canals and then to the
pancreatic duct till it reachs
-the juice contains enzymes
that will break diff. kind of
-The breakdown of
carbohydrates starts in the
mouth (by amylase) thats why
when we eat a bread we feel
its sugery taste.
Islets of Langerhans
"secretion goes directly
to the blood"
Does not help in
digestion, it produces
hormones which goes to
The most importnt
hormone is Insoline
(does not do
-Pencreatic amylase help in the
brek down of protiens, lipid,
Check out the video in the attachments (What do my pancreas do?)
-The major accessory
-The largest organ on our body about 1.5 kg
-Located beneath the diaphragm (the diaphragm is covering above the liver)
-It is covered by the peritoneum
-Divided into 2 main lobes: Left lobe and right lobe (larger)
-The 2 lobes are separated by part of the peritoneum, part of the connective tissue,
called falciforn ligament
-The falciforn ligament splits the liver into 2 regions
-When we look at the liver from the posterior (back) view, there is other 2 small lobes:
1) Caudate lobe
2) Quadrate lobe – because of the gallbladder which is hanging from the liver
(beneath the liver)
Note that: THE MAIN LOBES ARE RIGHT AND LEFT, AND FROM BEHIND
THERE ARE 2 others
-Blood supply of the liver:
A) Get blood from The Hepatic Portal Vein:
This vein comes from the intestine
In the intestine there are arteries, which passes through it. The food is digested there
the absorbed; the absorbed food will collect and go out of the intestine through the
portal vein, the portal vein will go to the liver [it is important for this food, before being
distributed all over the body , to go to the liver because many modification happens
inside the liver.
(Briefly, the food came from the intestine and won’t go directly to the different parts
of the body. They will gather through the hepatic portal vein and enter the kidney)[the
digested food will go through the hepatic portal vein to the liver.
B) The Hepatic Artery
Take oxygenated blood so that liver can survive
There are 2 ways in which the blood enters the liver, then bllod leaves through the
hepatic vein .
-The liver produces something called "bile". Bile flow through small canaliculi called "bile
canaliculi". These bil canaliculi will join eachother, like a tree, into" small bile ducts". All
small bile ducts make "right and left hepatic duct" - 2 main ductsm. The will join
togather into one duct called" common hepatic duct" then it goes to the "common bile
duct". The common bile duct goes inside the pencreas and join the pencriatic duct and
form small duct called "hepato pancreatic ampulla". The hepatopancriatic ampulla
empties the soulution (enzyme/ juice) in the "duodenal papilla".
Function of the liver
Digestive: bile salts
Excretory: get rid of bilirubin
very important for digestive of fat =
emulsification (like the way soap clean and
break down fat droplets)
a substance that is produced in the body
during the break down of RBC – the
accumulation of it is dangerous because it
can effect the brain etc. (babies
sometimes look yellow in color because
their liver isn't mature enough and can't
get rid of bilirubin. Excrete bilirubin
through the bile go to the duodenum then
to the stool.
Check out the video in the attachments (The liver and pancreas).
What is inside the liver?
*Sinusoids and bile canaliculi → small space between hepatocytes (liver calls) cords. Cells
take the food and convert it to useful things and it then return it back to the blood.
Important that blood passes through all these cells.
*Kupffer’s cells → immune calls present everywhere that catch any abnormal things "
-Hepatic triad (like triangle) locate between lobules
a. Most of blood comes from it/ it is the source of the blood
b. Contains hepatic vein + hepatic artery + bile ducts.
Other functions of the liver:
1-production of proteins: clotting proteins → help in stopping bleeding when getting an
injury - the liver produces it and the send it to the blood.
2-metabolism of nutrients: e.g. when we eat a lot of fat, liver convert it to cholesterol.
(it is needed in normal amounts but the excess of cholesterol is bad for us).
3-Detoxifications: Removal of toxics materials e.g. alcohol toxic will be filtered by the
liver. That’s why people who drink have liver problems.
#And if a substance cannot be detoxified, it will be captured and kept in the liver.
4-Storage of nutrients especially sugar (later use) when we are not hungry. When we are
hungry, sugar will be released to the blood. It is stored in the form of glycogen.
5-Immunity, as a filter through the kupffer’s cells.
6-Activation of vitamin D: Vitamin D is important for the bones and calcium metabolism.
We need the sun to get Vitamin D. Our liver do some modifications and then the sun
continues its job.
(storage of bile)
Location: hanging below the liver (we must look at the liver from behind to see it)
Function of the bile :
Bile, which collected from the liver, go through cystic duct and accumulate in the
gallbladder. And it is deconcentrated in the gallbladder because the bile absorb water
and make it more concentrated up to 10 times.
When we need it and we eat, the food will go to the duodenum and the gallbladder will
squeeze and empties the bile and it will go down and combine with the pancreatic duct
then go to the duodenum to do their function in the metabolism of fat.
Check the video in the attachments (Liver vedio)