So now let’s move on to the gallbladder and the biliary tree.
So this diagram we have seen many times before now.
As the liver lifted and we've exposed
the stomach and the lesser omentum.
And we can see that the liver
on its visceral, its more posterior surface
has the gallbladder attached to it.
We can see the gallbladder here, this little sack.
The gallbladder has a fundus right at the very tip
which is poking out from the under surface of the liver.
It has a body and it also has a neck.
And that neck gives rise to the cystic duct.
Again we can see we have a fundus
down here in this isolated diagram showing
component parts of the gallbladder.
We have a fundus here, we have a larger body
and then it take us down into this neck.
The neck is in continuous with the
cystic duct. We can see the cystic duct
here and what's happening
is the hepatocytes within
the liver are producing bile.
Now this bile needs to be stored and
it's concentrated. And it does that within the gallbladder.
So what here we have the liver
and we have our left and our right
hepatic ducts. These converge
into a common hepatic duct,
which unites with the cystic duct.
And this allows a pathway for bile
that's been produced in the
liver to be stored in the gallbladder.
So bile is then transferred
from the liver to the gallbladder.
Now it usually does this by passing
all the way down to the duodenum first.
So here we have got the bile duct.
The bile duct formed by the
union of the cystic duct
here and the common hepatic duct.
Where these two unite
we find the bile duct.
So what's happening.
Bile is produced in the liver.
Bile then runs all the way down through the bile duct
towards the duodenum.
If the sphincter that's guarding
this major duodenal papilla is closed
Then the liver will continue to produce
the bile but instead of being released back into the duodenum,
it's going to pass all the way
back up and go into the gallbladder.
So as bile is passing down
in this direction so if it's closed,
the entrance to the duodenum is
closed, then it will pass back up and be stored
in the gallbladder.
This means when in the gallbladder
it will be concentrated and then when need to be
outflow of bile can then enter into
the duodenum say one once you eat a particularly
fatty meal. And this
relationship forms part of the biliary tree
When we will look at the pancreas we will
consider the inputs from the pancreas via the pancreatic duct.
So, bile is stored and
concentrated in the gallbladder. And this is
if it becomes overly concentrated,
overly dehydrated can lead to gall stones.