Exam 3: Ch.8 Glands of Digestion Flashcards
What is the small organ inferior to the liver? What makes up the bulk of the organ? What connects to the other narrow part of it?
Gallbladder
- body is bulk of it
- cystic duct connects to narrow neck
What are the two functions of the Gallbladder?
- Store bile– can hold about 70ml
2. Concentrate bile
What are the two types of Bile we produce?
- Hepatic Bile = primary bile from liver
2. Cystic Bile = concentrated bile from gallbladder
What controls the release of bile?
controlled by CCK and the Vagus nerve
What is the surface epithelium of the Gallbladder? What type of cells does it contain?
simple columnar
Cells:
1. Clear Cells (aka cholangiocytes)
2. Brush Cells
What are the three organs we are discussing that are the Glands of Digestion?
- Gallbladder
- Pancreas
- Liver
Where are Clear cells located? What do they have many of and what is their function?
( = cholangiocytes)
In surface epithelium of mucosa of Gallbladder–> have many microvilli
Fxn: concentrate bile by absorbing water
What type of cells concentrates bile by absorbing water?
Clear cells (aka cholangiocytes)
Where are Brush Cells located? Are there a lot here? What is their function?
in surface epithelium of mucosa of gallbladder
few in number
produce mucinogen
Does the Gallbladder have a lamina propria? If so, describe it.
yes; loose and very vascular CT
What will the Neck posses of the the Lamina propria in the Gallbladder? What is the function?
small mucous glands
Fxn: to lubricate the narrow neck lumen
Does the Gallbladder have a Muscularis mucosa?
What about a Submucosa?
no; it is ABSENT
no; ABSENT!!! (very unusual)
Is the Muscularis Externa of the Gallbladder a normal or not normal pattern?
NOT normal pattern
consists of thin smooth ms layer with a DISorganized ms arrangement
Does the Gallbladder have adventitia or serosa or both?
mixed
- mostly serosa
- some adventitia – where is attaches to the liver
What surrounds the pancreas? What dive into the pancreas?
a thin CT capsule
septa dive into organ– creating lobules
What two portions does the pancreas contain? Which is larger?
- Endocrine Pancreas = Pancreatic Islets = Islets of Langerhans producing hormones
- Exocrine Pancreas = Serous acini producing digestive enzymes
- -> larger portion
What two things does the Exocrine Pancreas contain?
- Serous (pancreatic) Acini
2. Pancreatic Duct
What controls the secretion from the Serous (pancreatic) acini?
CCK and ACh form parasympathetic nerves
What gets secreted from the Pancreatic Ducts? What controls this?
secretes H2O and HCO3-
controlled by secretin and ACh from parasympathetic nerves
In the Pancreatic Ducts, what type of cells are located next to acinar cells?
Centroacinar cells
What produces an alkaline fluid with large quantities of bicarbonate ions in the pancreas? What is the function?
Centroacinar cells and cuboid cells in intercalated pancreatic ducts
buffer stomach chyme
What wraps the Pancreatic Ducts? What is the function of this?
collagen-rish CT
Fxn: to provide extra protection from possible leaking of digestive enzymes
What is the largest gland in the body with endocrine and exocrine function?
liver
What are the 5 general functions of the liver?
- Metabolism of lipids, carbs, and proteins
- production of blood proteins, factors, and substances
- detoxify blood
- produce heptic (primary) bile– an exocrine fxn
- store certain vitamins (vit A, Vit B12)
How are the Hexagonal-shaped lobules of the liver difficult to distinguish in humans?
due to lack of CT b/w lobules
What are the five cells types in the liver?
- Hepatocytes (MC)
- Kupffer cells
- Ito Cells = Hepatic Stellate Cells
- Pit cells
- Hepatic Progenitor Cells
What type of cells in the liver are microvilliated cuboidal cells possessing lateral bile canaliculi b/w adjacent hepatocytes?
Hepatocytes
What is the function of the Hepatocytes?
see most general functions??
How does Bile flow through the liver?
Bile move from the hepatocytes–> towards the Bile Duct Branch in the portal triad
How are the Hepatocytes arranged?
in rows b/w hepatic sinusoids like spoke of a wheel
What collects the bile in the liver secreted by hepatocytes?
Bile canaliculi
What are the resident macrophages in the liver? What do they develop from?
Kupffer cells (aka stellate macrophages)
develop form monocytes
What is the function of the Kupffer cells?
phagocytis of debris and aged RBC’s
act as an APC
What is another name for Ito Cells in the liver? What is their function?
Hepatic Stellate Cells
- store lipids for immediate use
- store Vit A
- produce collagen I, III, IV, and growth factors
What cells in the liver phagocytosis debris and aged RBC’s and act as APC?
Kupffer cells (aka stellate macrophages)
What cells in the liver store lipids for immediate use, store vit A, and produce collagen I, III, IV, and growth factors?
Ito Cells (aka Hepatic Stellate Cells
What do we think Pit cells of the liver have the ability to do?
maybe natural killer cells?
What allows the liver to have its regenerative capabilities? What may these cells develop from?
Hepatic Progenitor Cells
may develop from Oval cells
What four branches does the Portal Triad consist of?
- The hepatic artery
- the portal vein
- the bile duct
- lymph vessels
What are Hepatic Sinusoids? What are they found b/w? What do they carry*?
dilated, fenestrated thin walled vessels found b/w the rows of hepatocytes
carry a mixture of venous (~75%) and arterial blood (~25%)
What collects blood from the hepatic sinudoids? Where is this located?
Central Vein
fenestrated thin walled vessels
located in middle of classic liver lobule
What are the dilated, fenestrated thin walled vessels found b/w the rows of hepatocytes? What does it carry*?
Hepatic Sinusoids
carry mixture of venous (~75%) and arterial blood (~25%)
How does the blood flow in the liver?
blood flows from the —> towards the
What is the space b/w the hepatocytes and the fenestrated hepatic sinusoids where blood can directly contact the microvilliated surfaces of the hepatoyctes?
Space of Disse (aka perisinusoidal space)
Is the blood going fast or slow through the Space of Disse? Why?
flows flow enough so cells can interact with blood and its contents
(this is why liver can take over functioning for the spleen in ~24-48 hours)
How quick can the liver take over functioning for the spleen?
~24-48 hours
T/F. The bile and blood travel in the same direction through the liver.
False
Bile–> from hepatocytes towards bile duct branch in the portal triad
Blood–> from portal triad toward central vein
T/F. The blood and bile stay separate in the liver.
True
What is the name of the dense irregular CT covered with serosa of the liver?
Glisson’s Capsule
other CT is limited in the human liver
What are the two reason for why the Space of Disse is important?
- blood can directly contact the hepatocytes
2. Slows blood flow so cells can interact with blood and its contents