GI Anatomy Flashcards
The GI organs reside in the _ cavity which is lined with _
The GI organs reside in the abdominopelvic cavity which is lined with peritoneum
The peritoneum is a thin, transparent _ membrane that lines the abdominopelvic cavity
The peritoneum is a thin, transparent serous membrane that lines the abdominopelvic cavity
* Continuous layer of peritoneum seen in sagittal section
The parietal layer of the peritoneum is found _
The parietal layer of the peritoneum is found lining the inside of the body wall
The visceral layer of the peritoneum is found _
The visceral layer of the peritoneum is found adhered to the surface of the organs
The peritoneal cavity is the space between the two layers of peritoneum; it contains a thin film of serous fluid that has _ function
The peritoneal cavity is the space between the two layers of peritoneum; it contains a thin film of serous fluid that facilitates movement of the organs during digestion and respiration
* Provides a protective function
* Also helps us classify organs (intraperitoneal vs retroperitoneal)
The peritoneal cavity is divided into two spaces; _ and _
The peritoneal cavity is divided into two spaces; greater sac and lesser sac
* The greater sac includes the vast majority of the peritoneal cavity
The lesser sac is a small extension of the peritoneal cavity found _
The lesser sac is a small extension of the peritoneal cavity found posterior to the stomach
* Also called the “omental bursa”
The entrance to the lesser sac is through a small opening referred to as the _
The entrance to the lesser sac is through a small opening referred to as the epiploic foramen (foramen of Winslow)
The _ peritoneum forms important support structures like mesentaries, omenta, and peritoneal ligaments
The visceral peritoneum forms important support structures like mesentaries, omenta, and peritoneal ligaments
* These are collectively called peritoneal reflections
_ is a double layer of visceral peritoneum that connects the stomach and proximal duodenum to another organ
Omentum is a double layer of visceral peritoneum that connects the stomach and proximal duodenum to another organ
The greater omentum is an apron-like peritoneum that originates from the _ and drapes over the _
The greater omentum is an apron-like peritoneum that originates from the greater curvature of the stomach/ proximal duodenum and drapes over the small intestines
The lesser omentum originates from the _ and attaches to the _
The lesser omentum originates from the lesser curve of the stomach and attaches to the liver
The lesser omentum encompasses two important ligaments _ and _
The lesser omentum encompasses two important ligaments, the hepatogastric ligament (1) and hepatoduodenal ligament (2)
The portal triad is found beneath the _ ligament
The portal triad is found beneath the hepatoduodenal ligament
The portal triad includes:
The portal triad includes:
1. Portal vein
2. Proper hepatic artery
3. Common bile duct
(Mesentery/ Omentum) is a double layer of visceral peritoneum that connects organs to the posterior abdominal wall AND transmits blood vessels and nerves
Mesentery is a double layer of visceral peritoneum that connects organs to the posterior abdominal wall AND transmits blood vessels and nerves
Name the three major mesenteries of the gut
- Mesentery (proper) of the small intestines
- Transverse mesocolon
- Sigmoid mesocolon
The mesentery of the small intestines has a fan shape and connects the _ and _ to the posterior abdominal wall
The mesentery of the small intestines has a fan shape and connects the jejunum and ileum to the posterior abdominal wall
The mesentery that connects the transverse colon to the posterior abdominal wall is called the _
The mesentery that connects the transverse colon to the posterior abdominal wall is called the transverse mesocolon
The mesentery that connects the sigmoid colon to the posterior abdominal wall is called the _
The mesentery that connects the sigmoid colon to the posterior abdominal wall is called the sigmoid mesocolon
The _ ligament anchors the liver to the anterior abdominal wall
The falciform ligament anchors the liver to the anterior abdominal wall
The _ ligament connects the fetal umbilical vein within the falciform ligament
The round ligament connects the fetal umbilical vein within the falciform ligament
The round ligament is also called the _
The round ligament is also called the ligamentum teres
The _ ligaments extend from the liver to the diaphragm
The coronary ligaments extend from the liver to the diaphragm
The connection of the greater omentum to the spleen is called the _ portion
The connection of the greater omentum to the spleen is called the gastrosplenic (portion of the greater omentum)
The connection of the greater omentum to the diaphragm is called the _
The connection of the greater omentum to the diaphragm is called the gastrophrenic
The connection of the greater omentum to the transverse colon is called the _
The connection of the greater omentum to the transverse colon is called the gastrocolic
The peritoneum that spans from the spleen to the kidney is called the _
The peritoneum that spans from the spleen to the kidney is called the splenorenal
Most of our GI organs are (intraperitoneal/ retroperitoneal)
Most of our GI organs are intraperitoneal meaning they are completely surrounded by the visceral peritoneum
Name the retroperitoneal organs
SAID PUCKER
* Suprarenal glands
* Aorta
* IVC
* Duodenum (except for the first part)
* Pancreas (except for the tail)
* Ureters
* Colon (ascending and descending)
* Kidneys
* Esophagus (distal)
* Rectum
The head and body of the pancreas are (intraperitoneal/ retroperitoneal)
The head and body of the pancreas are retroperitoneal
The tail of the pancreas is (intraperitoneal/ retroperitoneal)
The tail of the pancreas is intraperitoneal
The first portion of the duodenum is (intraperitoneal/ retroperitoneal)
The first portion of the duodenum is intraperitoneal
The second, third, and fourth portions of the duodenum are (intraperitoneal/ retroperitoneal)
The second, third, and fourth portions of the duodenum are retroperitoneal
The transverse colon is (intraperitoneal/ retroperitoneal)
The transverse colon is intraperitoneal
The ascending colon is (intraperitoneal/ retroperitoneal)
The ascending colon is retroperitoneal
The descending colon is (intraperitoneal/ retroperitoneal)
The descending colon is retroperitoneal
The sigmoid colon is (intraperitoneal/ retroperitoneal)
The sigmoid colon is intraperitoneal
Secondarily retroperitoneal organs are organs that _
Secondarily retroperitoneal organs are organs that were initially intraperitoneal during development but later became fused with the posterior abdominal wall and only covered by visceral peritoneum on one side
Secondarily retroperitoneal organs include:
Secondarily retroperitoneal organs include:
* Ascending/descending colon
* Duodenum (2nd, 3rd, 4th)
* Pancreas (except the tail)
GI organs are vascularized by three main arteries that arise from the abdominal aorta _ , _ , and _
GI organs are vascularized by three main arteries that arise from the abdominal aorta celiac artery , superior mesenteric artery , and inferior mesenteric artery
The nutrient-rich venous blood that is drained out of the GI organs first goes through the _ to the _
The nutrient-rich venous blood that is drained out of the GI organs first goes through the portal venous system to the liver
The venous blood from the GI organs first goes to the liver for _ before being sent to the _
The venous blood from the GI organs first goes to the liver for extraction of nutrients and removal of toxins before being sent to the IVC/ right atrium
* GI –> portal venous system –> liver sinusoids –> hepatic veins –> IVC
During embryonic development, the primitive gut tube is divided into 3 sections, _ , _ , and _
During embryonic development, the primitive gut tube is divided into 3 sections, foregut , midgut , and hindgut
* Each section is vascularized by its own artery
The foregut is vascularized by the _
The foregut is vascularized by the celiac artery
The midgut is vascularized by the _
The midgut is vascularized by the SMA
The hindgut is vascularized by the _
The hindgut is vascularized by the IMA
The foregut gives rise to _ structures
The foregut gives rise to…
* Distal esophagus
* Stomach
* Liver
* Gallbladder
* Proximal half of duodenum
* Most of the pancreas
* Spleen
The midgut gives rise to _
The midgut gives rise to…
* Distal half of the duodenum
* Jejunum
* Ileum
* Cecum
* Appendix
* Ascending colon
* Two-thirds of the transverse colon
The hindgut gives rise to the _
The hindgut gives rise to…
* Distal 1/3rd transverse colon
* Descending colon
* Sigmoid colon
* Rectum
The stomach and spleen are vascularized by the _
The stomach and spleen are vascularized by the celiac artery
The pancreas is vascularized by the _ and _ arteries
The pancreas is vascularized by the celiac and superior mesenteric arteries
The small intestines are vascularized by the _
The small intestines are vascularized by the superior mesenteric artery
The colon is vascularized by the _ and _
The colon is vascularized by the SMA and IMA
The celiac trunk arises from the aorta at vertebral level _
The celiac trunk arises from the aorta at vertebral level T12
The celiac trunk gives rise to 3 major branches:
The celiac trunk gives rise to 3 major branches:
Left gastric artery
Splenic artery
Common hepatic artery
The left gastric artery (off the celiac trunk) supplies the _ and _
The left gastric artery (off the celiac trunk) supplies the lesser curve of the stomach and abdominal esophagus
The splenic artery supplies the _ and also feeds into _ and _
The splenic artery supplies the spleen and also feeds into gastric arteries and left gastro-epiploic to supply the greater curvature of the stomach
The common hepatic artery has two major branches _ and _
The common hepatic artery has two major branches proper hepatic artery and gastroduodenal artery
The proper hepatic artery supplies the _
The proper hepatic artery supplies the liver
The right gastric artery comes off of the _
The right gastric artery comes off of the proper hepatic artery
The gastroduodenal artery supplies the _
The gastroduodenal artery supplies the proximal duodenum
The gastroduodenal artery gives rise to the _ and _
The gastroduodenal artery gives rise to the right gastroepiploic and anterior & posterior superior pancreaticoduodenal arteries
The superior mesenteric artery arises from the aorta at the _ vertebral column level
The superior mesenteric artery arises from the aorta at the L1 vertebral column level
The SMA and its branches vascularizes the _ duodenum, head of the pancreas, jejunum, ileum, cecum, appendix, ascending colon, 2/3rds of the transverse colon
The SMA and its branches vascularizes the distal duodenum, head of the pancreas, jejunum, ileum, cecum, appendix, ascending colon, 2/3rds of the transverse colon
The right colic artery (SMA) vascularizes the _
The right colic artery (SMA) vascularizes the ascending colon
The middle colic artery (SMA) vascularizes the _
The middle colic artery vascularizes the transverse colon
The _ artery (SMA) vascularizes the cecum
The iliocolic artery (SMA) vascularizes the cecum
The inferior mesenteric artery arises from the aorta at the _ vertebral column level
The inferior mesenteric artery arises from the aorta at the L3 vertebral column level
The 3 major branches of the IMA include:
The 3 major branches of the IMA include:
* Left colic artery
* Sigmoidal arteries
* Superior rectal artery
The _ artery traverses along the mesenteric side of the colon forming an important anastomosis along the colon
The marginal artery traverses along the mesenteric side of the colon forming an important anastomosis along the colon
The _ artery (IMA) vascularizes the descending colon and the distal 1/3rd of the transverse colon
The left colic artery (IMA) vascularizes the descending colon and the distal 1/3rd of the transverse colon
The _ arteries (IMA) vascularize the sigmoid colon
The sigmoidal arteries (IMA) vascularize the sigmoid colon
* We have 2-3 arteries
The _ arteries (IMA) supply the rectum
The superior rectal arteries (IMA) supply the rectum
Recall that the IMA vascularizes the hindgut, which involves the _
Recall that the IMA vascularizes the hindgut, which involves the distal 1/3rd transverse colon, descending colon, sigmoid, rectum
(ANS/ENS) neural regulation coordinates peristalsis, secretory activity, and GI blood flow
ENS neural regulation coordinates peristalsis, secretory activity, and GI blood flow
(True/False) The ENS can direct all functions of the GIT in the absence of input from the ANS
True; The ENS can direct all functions of the GIT in the absence of input from the ANS
* The autonomic nervous system modulates ongoing GI activity through its innervation of the plexuses
The ENS involves neurons contained within the wall of the gut; mainly the _ and _ plexus
The ENS involves neurons contained within the wall of the gut; mainly the Submucosal (Meissner) plexus and Myenteric (Auerbach) plexus
The parasympathetic innervation to the gut is via two nerves, the _ and _
The parasympathetic innervation to the gut is via two nerves, the vagus and pelvic splanchnic nerves
Cranial nerve X innervates the (foregut/midgut/hindgut)
Cranial nerve X (vagus) innervates the forgut and midgut
The pelvic splanchnic nerves innervate the _ organs
The pelvic splanchnic nerves innervate the hindgut organs
* Distal 1/3rd of the transverse colon, descending, sigmoid, rectum
The long preganglionic parasympathic vagus nerve cell bodies originate in the _
The long preganglionic parasympathic vagus nerve cell bodies originate in the brainstem
The long preganglionic parasympathic pelvic splanchnic nerve cell bodies originate in the _
The long preganglionic parasympathic pelvic splanchnic nerve cell bodies originate in the S2-S4 spinal cord
Parasympathic activity has _ effect on GI organs
Parasympathic activity increases peristalsis, secretions, motility, absorption
The preganglionic sympathetic nerves that innervate the gut originate in spinal cord segments _
The preganglionic sympathetic nerves that innervate the gut originate in spinal cord segments T5-L2
The greater splanchnic nerves originate from _ spinal cord segments
The greater splanchnic nerves originate from T5-T9
The lesser splanchnic nerves originate from _ spinal cord segments
The lesser splanchnic nerves originate from T10-T11
The least splanchnic nerve originates from _ spinal cord segments
The least splanchnic nerve originates from T12
The lumbar splanchnic nerves originate from _
The lumbar splanchnic nerves originate from L1-L2
We have three pre-vertebral or aortic ganglia where sympathetic preganglionic nerves synapse:
We have three pre-vertebral or aortic ganglia where sympathetic preganglionic nerves synapse:
1. Celiac ganglia
2. Superior mesenteric ganglia
3. Inferior mesenteric ganglia
Sympathetic innervation has what effect on GIT?
Sympathetic innervation decreases peristalsis, secretions, motility, absorption
Pain from the foregut organs tend project to _ spinal cord segments and dermatomes
Pain from the foregut organs tend project to T5-T9 spinal cord segments and dermatomes
Pain from the midgut organs tend project to _ spinal cord segments and dermatomes
Pain from the midgut organs tend project to T10-T11 spinal cord segments and dermatomes
Pain from the hindgut organs tend project to _ spinal cord segments and dermatomes
Pain from the hindgut organs tend project to T12-L2 spinal cord segments and dermatomes
The visceral (inferior) surface of the liver reveals two additional lobes, _ and _
The visceral (inferior) surface of the liver reveals two additional lobes, quadrate and caudate
The caudate and quadrate lobes are functionally part of the (right/left) liver lobe
The caudate and quadrate lobes are functionally part of the left lobe
The _ is a remnant of the ductus venosus that can be seen from the visceral (inferior) side of the liver
The ligamentum venosum is a remnant of the ductus venosus that can be seen from the visceral (inferior) side of the liver
The _ is where the portal triad structures enter and exit the liver
The porta hepatis is where the portal triad structures enter and exit the liver
The _ conveys nutrient rich venous blood from the GIT to the liver (making up the majority of the liver’s blood supply)
The portal vein conveys nutrient rich venous blood from the GIT to the liver (making up the majority of the liver’s blood supply)
The _ (from the celiac trunk) conveys oxygenated blood to the liver
The proper hepatic artery (from the celiac trunk) conveys oxygenated blood to the liver
The incoming blood going to the liver flows through _ which are specialized capillaries which allow processing to occur
The incoming blood going to the liver flows through sinusoids which are specialized capillaries which allow processing to occur
Venous blood exits the liver via the _ to the _
Venous blood exits the liver via the hepatic veins to the IVC
Branching of the liver’s vasculature divides the liver into _ functional segments
Branching of the liver’s vasculature divides the liver into 8 functional segments
One of the key functions of the liver is to produce and secrete _ for the digestion of fats
One of the key functions of the liver is to produce and secrete bile for the digestion of fats
* The biliary system transports bile from the hepatocytes to the duodenum
The right and left hepatic ducts (from the liver) come together to form the _
The right and left hepatic ducts (from the liver) come together to form the common hepatic duct
The _ is the vessel leaving the gallbladder that will join the common hepatic duct
The cystic duct is the vessel leaving the gallbladder that will join the common hepatic duct
The cystic duct and common hepatic duct join to form the _
The cystic duct and common hepatic duct join to form the common bile duct
The _ transports bile into the duodenum
The common bile duct transports bile into the duodenum
The common bile duct joins the main pancreatic duct at the _
The common bile duct joins the main pancreatic duct at the ampulla of vater
The ampulla of vater opens into the _ (in the duodenum)
The ampulla of vater opens into the major duodenal papilla (in the duodenum)
The muscle surrounding the ampulla is called the _ ; it is regulated by CCK
The muscle surrounding the ampulla is called the sphincter of oddi ; it is regulated by CCK
Venous blood from the inferior esophagus to the superior rectum travels back to the liver via _ before the blood eventually returns to the heart
Venous blood from the inferior esophagus to the superior rectum travels back to the liver via hepatic portal system before the blood eventually returns to the heart
* The hepatic portal system allows liver to absorb nutrients but also detoxifies metabolites
The veins that coalesce to form the portal vein include:
The veins that coalesce to form the portal vein include:
* Splenic vein
* Superior mesenteric vein
* Inferior mesenteric vein
* Gastric vein (not a major contributor)
Portacaval anastomoses are naturally occurring venous connections that “shunt” between veins of the _ and veins that _
Portacaval anastomoses are naturally occurring venous connections that “shunt” between veins of the portal system and veins that drain into IVC
Name the (4) main portacaval anastomoses:
Name the (4) main portacaval anastomoses:
1. Left gastric + esophageal
2. Paraumbilical + superficial epigastric veins
3. Superior rectal veins + middle/inferior rectal veins
4. Veins draining retroperitoneal organs + IVC
Esophageal varices may form from a natural anastomose between the esophageal veins and the _
Esophageal varices may form from a natural anastomose between the esophageal veins and the left gastric vein
Paraumbilical varices result from the anastomose between _ and _
Paraumbilical varices result from the anastomose between paraumbilical veins and superficial epigastric veins
Why is it clinically significant that the veins that contribute to the portal vein do not have valves?
No valves –> allows retrograde flow
Portal hypertension (often from cirrhosis) can cause blood in the portal vein and its tributaries to “back up” and flow retrograde into the portocaval anastomoses
When anastomotic “shunts” become overloaded with venous blood we end up with _
When anastomotic “shunts” become overloaded with venous blood we end up with varices
Portal hypertension may cause blood from the left gastric vein to flow into the _
Portal hypertension may cause blood from the left gastric vein to flow into the esophageal veins –> esophageal varices
Blood from the paraumbilical veins can back up into the _ veins and form _
Blood from the paraumbilical veins can back up into the epigastric veins and form caput medusae
Blood from the superior rectal vein can back up into the _
Blood from the superior rectal vein can back up into the middle/inferior rectal veins (which eventually flow into the IVC) and we form hemorrhoids
The _ is a transition in the anal canal that marks the end of the hindgut and the beginning of the anus
The pectinate line is a transition in the anal canal that marks the end of the hindgut and the beginning of the anus
