Accessory Organs Of Digestion Flashcards
What kind of saliva does the parotid gland secrete?
Serous saliva
What is the name of the duct that secretes saliva from the parotid gland?
What is its pathway?
Stenston Duct
Arises from anterior surface of the gland, transverses the masseter muscle, turns into the buccal fat pad and pierces the buccinator, opens into the oral cavity near the 2nd upper molar
What 3 important structures pass through the parotid gland?
What do they divide into? (Or are formed by?)
Facial nerve - divides into 5 terminal branches to innervate muscles of facial expression
External carotid artery - divides into maxillary and superficial temporal artery
Retromandibular vein - formed by convergence of superficial temporal and maxillary veins
What is the parasympathetic innervation of the parotid gland?
Glossopharyngeal nerve, synapses with otic ganglion
Auriculotemporal nerve carries parasympathetic fibres from the otic ganglion
This results in an increase in saliva production
What kind of secretion does the submandibular gland secrete?
Mixed serous and mucous secretion
What is the name of the submandibular duct?
What is its pathway?
Wharton’s Duct
Emerges anteromedial from the deep arm of the gland, ascends on its course to open a the base of the lingual frenulum bilaterally
What is the parasympathetic innervation of the submandibular and sublingual gland?
Chorda tympani synapses at the submandibular ganglion
Post ganglion innervation of the gland
This increases saliva secretion
What kind of secretion do the sublingual glands secrete?
Mucous secretion
What is the name of the sublingual duct?
Barholin duct
What are the two functions of the pancreas?
Exocrine - secrete digestive juices
Endocrine - secrete hormones to control glucose levels
What are the 5 anatomical parts of the pancreas?
Head - lies in C shaped curve created by duodenum
Uncinate process - projection from lower part of head
Neck - located between head and body
Body - centrally located
Tail - left end of pancreas that lies in close proximity to the spleen
What is the only part of the pancreas that is intraperitoneal?
The tail
Describe the course of the pancreatic duct?
Beings at the tail of the pancreas
Runs the length of the pancreas right through body into the head, turns inferiorly in the head
In the head it gives off the accessory pancreatic duct
In the lower head it combines with the common bile duct to form the hepatopancreatic ampulla (ampulla of vater)
Where does the hepatopancreatic ampulla open into?
The major duodenal papilla
In the 2nd (descending)part of the duodenum
How are the secretions at the major duodenal papilla controlled
By the sphincter of oddi - surrounds the ampulla of vater and acts as a valve
Where does the accessory pancreatic duct open into?
The minor duodenal papilla
What do the pancreatic duct and the bile duct combine to make?
The ampulla of vater
What is the arterial supply to the pancreas?
Splenic artery - supplies the body and neck
Gastroduodenal artery - splits into the anterior superior and posterior superior pancreaticoduodenal artery to supply the head
Superior mesenteric artery - splits into the anterior inferior and posterior inferior pancreaticoduodenal artery to supply the head
What is the venous drainage of the pancreas?
Superior mesenteric vein
Splenic vein
What is the lymphatic drainage of the pancreas?
Pancreaticosplenal nodes
Pyloric nodes
What are the two surfaces of the liver?
Diaphragmatic Surface - anterosuperior surface of the liver which is smooth and convex
Visceral Surface - posteroinferior surface of the liver, moulded by the shape of the surrounding organs
What is the bare area of the liver?
What is it bounded by?
Part of the liver on the diaphragmatic surface where there is no intervening peritoneum between the liver and the diaphragm
Bounded by the anterior coronary and posterior coronary ligament
What are the three hepatic recesses?
Subphrenic space (left and right) - located between the diaphragm and the liver
Subheptic space - located between inferior surface of liver and transverse colon
Hepatorenal recess - located between the right side of liver and the right kidney
What is another name for the hepatorenal recess?
Morison’s Pouch
What is the falciform ligament?
What is it a remnant of?
Ligament attached to the anterior surface of the liver to the anterior abdominal wall, divides the left and right lobes
Free edge contains the ligamentum teres - remnant of the umbilical vein
What is the fibrous layer that covers the liver called?
Glisson’s capsule
What are the four lobes of the liver?
Right
Left
Caudate
Quadrate
What is the ligamentum venosum a remnant of?
The fetal ductus venousus
What is the portal triad composed of?
Branch of hepatic artery entering the liver
Branch of hepatic portal vein entering the liver
Branch of bile duct leaving the liver
Which two veins combine to make the portal vein?
Where does this occur?
Splenic vein and Superior mesenteric
Occurs at the level of L2 posterior to the neck of the pancreas
What is the blood supply to the liver
Hepatic artery proper (25%)
Hepatic portal vein (75%)
What is the venous drainage of the liver?
Left and right hepatic veins - drain into the inferior vena cava
What is the purpose of portacaval anastomoses?
If portal circulation to the liver is obstructed, then blood can return to the heart via the systemic circulation
What are the four site of portacaval anastomoses?
Inferior oesophagus
Upper anal canal
Secondary retroperitoneal structures
Paraumbillical area of anterior abdominal wall
Describe the portacaval anastomoses at the inferior oesophagus
Portal drainage - left gastric vein into portal vein
Systemic drainage - azygos vein into IVC
Describe the portacaval anastomoses at the upper anal canal
Portal drainage - superior rectal veins drain into portal system
Systemic drainage - middle and inferior rectal veins drain int internal iliac and internal pudendal which drain into IVC
Describe the portacaval anastomoses at the umbilicus
Portal drainage - paraumbilical veins drain into portal system
System drainage - superficial epigastric veins drain into axillary or femoral veins which drain into IVC
What is the lymphatic drainage from the liver
Hepatic lymph nodes (lie in the lesser omentum) Drain into coeliac lymph nodes Drain into intestinal trunk Drain into cysterna chyli Drain into thoracic duct
What is the storage capacity of the gall bladder?
30-50mL
Where does the gall bladder lie?
On the visceral surface of the right lobe of the liver in a fossa between the right and quadrate lobes
What are the three parts of the gall bladder?
Fundus
Body
Neck
What is Hartmann’s pouch?
A mucosal fold located in the neck of the gall bladder, where gallstones commonly become lodged
Describe the route of bile through the Biliary tree
Begins at the left and right hepatic ducts
Unite to form common hepatic duct
Unite with cystic duct from gall bladder to form common bile duct
Combine with pancreatic duct to form ampulla of vater
Empties into duodenum at major duodenal papilla
How is secretion of bile controlled?
By CCK release from enteroendocrine cells in duodenum - which is triggered by presence of fat in duodenum
This causes sphincter of oddi to relax
It also causes gall bladder to contract
What is the arterial supply of the gall bladder
Cystic artery - branch of right hepatic artery
What is the venous drainage of the gall bladder?
Dependant on area of the gall bladder:
Fundus and body - drain into hepatic sinusoids
Neck and cystic duct - drain into cystic vein
What is the lymphatic drainage of the gall bladder?
Cystic node
Where is the quadrate lobe found?
In between the left lobe and the gall bladder
