LESSON 10: THE DIGESTIVE SYSTEM
LBYGEZO (Lab)
that enter the alimentary canal through
ducts
INTRODUCTION
HISTOLOGY OF LIVER
● the Digestive System is concerned
with:
○ ingestion of food
○ physical and chemical
digestion of food
○ absorption of nutrient
molecules ● Central Vein - at the center of the
○ elimination of undigested lobule
remains ● Hepatocytes - scientific term for
● the system includes the Digestive liver cells; radiating from the
Tract or Alimentary Canal and the central vein that are polygonal
digestive glands associated with it shaped and arranged into cords or
plates; basic unit of the liver
ADDITIONAL INFO ● Sinusoid - act like pathways or
capillaries from the central vein;
● the toad has a complete spaces in between the hepatic
digestive tract, with two plates that lead toward the
openings – mouth and cloaca periphery of the hepatic lobule
● the main parts of the tract are: ● Canaliculus - are the sites where
mouth, oral or buccal cavity, the bile is secreted by the
pharynx, esophagus, hepatocytes
stomach, small intestine, large ● Portal Triad - very essential in the
intestine, rectum and cloaca assessment of the liver biopsy;
● the digestive glands include the composes of the following:
liver, gallbladder, and the ○ portal vein
pancreas ○ hepatic artery
○ bile duct
NOTE: these glands are not found within ● Portal Vein - venous drainage of
the tract but they secrete digestive juices liver; thin walled
1
, LESSON 10: THE DIGESTIVE SYSTEM
LBYGEZO (Lab)
● Hepatic Artery - blood supply; has
thick tunica intima
● Bile Duct - site of drainage by the
bile; simple cuboidal epithelium
● Liver Lobule - encompases all
parts; site of detoxification, enzyme
synthesis, clotting factor synthesis;
separated from each other by
connective tissue partition or
septa; one unit
● Liver - very essential in the
function of the digestive tract;
metabolizes the alcohol
ADDITIONAL INFO
● Central Vein - is the main
accessory blood supply, so the
further away the hepatocytes
they will be the first to be
damaged when there is a
decrease in blood supply
● Liver Enzymes - determinant
that the whole liver parenchyma
is damaged
● Pancreas - has both the endocrine
NOTE: the liver needs to be damaged by and exocrine functions
80-90% in order to secrete liver enzymes ● Head - near the duodernum
● Ampulla of Vater - small opening
HISTOLOGY OF PANCREAS where the cystic duct, common bile
duct opens and where the
pancreatic duct drains
● Pancreatic Duct - also called as
duct of Wirsung
● Accessory Pancreatic Duct - also
called as duct of Santorini;
contains the following:
○ Alpha Cell - glucagon
○ Beta Cell - insulin
○ Delta Cell - somatostatin
● Acinar Cells - one responsible for
the secretion of enzymes
● Pancreatic Acini - surrounding
rims that secrete amylase, lipase
and other enzymes to digest
macromolecules; consists of
pyramidal-shaped cells
surrounding a lumen
● Islets of Langerhans - are within
the masses of acini cells that are
isolated pancreatic islets; have rich
capillary network; perform the
endocrine function of the pancreas
2
LBYGEZO (Lab)
that enter the alimentary canal through
ducts
INTRODUCTION
HISTOLOGY OF LIVER
● the Digestive System is concerned
with:
○ ingestion of food
○ physical and chemical
digestion of food
○ absorption of nutrient
molecules ● Central Vein - at the center of the
○ elimination of undigested lobule
remains ● Hepatocytes - scientific term for
● the system includes the Digestive liver cells; radiating from the
Tract or Alimentary Canal and the central vein that are polygonal
digestive glands associated with it shaped and arranged into cords or
plates; basic unit of the liver
ADDITIONAL INFO ● Sinusoid - act like pathways or
capillaries from the central vein;
● the toad has a complete spaces in between the hepatic
digestive tract, with two plates that lead toward the
openings – mouth and cloaca periphery of the hepatic lobule
● the main parts of the tract are: ● Canaliculus - are the sites where
mouth, oral or buccal cavity, the bile is secreted by the
pharynx, esophagus, hepatocytes
stomach, small intestine, large ● Portal Triad - very essential in the
intestine, rectum and cloaca assessment of the liver biopsy;
● the digestive glands include the composes of the following:
liver, gallbladder, and the ○ portal vein
pancreas ○ hepatic artery
○ bile duct
NOTE: these glands are not found within ● Portal Vein - venous drainage of
the tract but they secrete digestive juices liver; thin walled
1
, LESSON 10: THE DIGESTIVE SYSTEM
LBYGEZO (Lab)
● Hepatic Artery - blood supply; has
thick tunica intima
● Bile Duct - site of drainage by the
bile; simple cuboidal epithelium
● Liver Lobule - encompases all
parts; site of detoxification, enzyme
synthesis, clotting factor synthesis;
separated from each other by
connective tissue partition or
septa; one unit
● Liver - very essential in the
function of the digestive tract;
metabolizes the alcohol
ADDITIONAL INFO
● Central Vein - is the main
accessory blood supply, so the
further away the hepatocytes
they will be the first to be
damaged when there is a
decrease in blood supply
● Liver Enzymes - determinant
that the whole liver parenchyma
is damaged
● Pancreas - has both the endocrine
NOTE: the liver needs to be damaged by and exocrine functions
80-90% in order to secrete liver enzymes ● Head - near the duodernum
● Ampulla of Vater - small opening
HISTOLOGY OF PANCREAS where the cystic duct, common bile
duct opens and where the
pancreatic duct drains
● Pancreatic Duct - also called as
duct of Wirsung
● Accessory Pancreatic Duct - also
called as duct of Santorini;
contains the following:
○ Alpha Cell - glucagon
○ Beta Cell - insulin
○ Delta Cell - somatostatin
● Acinar Cells - one responsible for
the secretion of enzymes
● Pancreatic Acini - surrounding
rims that secrete amylase, lipase
and other enzymes to digest
macromolecules; consists of
pyramidal-shaped cells
surrounding a lumen
● Islets of Langerhans - are within
the masses of acini cells that are
isolated pancreatic islets; have rich
capillary network; perform the
endocrine function of the pancreas
2
