Stomach Flashcards
The gastrointestinal tract begins as a single tube of endoderm but transforms into ____
the alimentary tract and its associated glands.
Endoderm Derivatives - the Gut Tube, Yolk Sac, and Allantois
Trilaminar embryo folds, creates body wall and enclose gut tube
→ As the body wall folds, ___ and ___ extend from it at umbilicus
definitive yolk sac and umbilical cord
Endoderm Derivatives - the Gut Tube, Yolk Sac, and Allantois
Trilaminar embryo folds, creates body wall and enclose gut tube
→ As the body wall folds, definitive yolk sac and umbilical cord extend from it at umbilicus
→Another small extension of gut tube which is ___ extends into the umbilical cord
allantois
Endoderm Derivatives - the Gut Tube, Yolk Sac, and Allantois
Endoderm of gut tube is in contact with overlying ectoderm at ____ and ____
→ once these membranes rupture, amniotic fluid will enter gut tube
oropharyngeal membrane and cloacal membrane
Endoderm Derivatives - the Gut Tube, Yolk Sac, and Allantois
Endoderm of gut tube is in contact with overlying ectoderm at oropharyngeal membrane and cloacal membrane
→ once these membranes rupture, ____ will enter gut tube
amniotic fluid
Gut Tube Membranes and Vitelline Duct
Yolk sac extends off of midgut region of gut tube, connected by ____
vitelline duct
Endoderm Derivatives - the Gut Tube, Yolk Sac, and Allantois
→ identify
Endoderm Derivatives - the Gut Tube, Yolk Sac, and Allantois
→ identify
Gut Tube Membranes and Vitelline Duct
→ identify
Mesenteries
Gut tube itself originates from (1)____ and is surrounded by (2)____ which forms structures surrounding gut tube and mesentery that connects it to body wall
- endoderm
- splanchnic layer of lateral plate mesoderm,
Blood Supply to Regions of the Gut Tube
→ As the body elongates, the arteries supplying the gut tube will subdivide into _______ (3), supplying the foregut, midgut and hindgut.
- endoderm
- splanchnic layer of lateral plate mesoderm,
Mesenteries
Gut tube itself originates from endoderm and is surrounded by splanchnic layer of lateral plate mesoderm, which forms structures surrounding gut tube and ____ that connects it to body wall
mesentery
Mesenteries
Gut tube itself originates from endoderm and is surrounded by splanchnic layer of lateral plate mesoderm, which forms structures surrounding gut tube and mesentery that connects it to body wall
→ Nerves and vessels that travel to and from gut tube are within ____
mesentery
Mesenteries - 5 weeks
→ identify
Blood Supply to Regions of the Gut Tube
→ As the body elongates, the arteries supplying the gut tube will subdivide into ___, supplying the foregut, midgut and hindgut.
the celiac, superior mesenteric, and inferior mesenteric arteries
Blood Supply to Regions of the Gut Tube
→ As the body elongates, the arteries supplying the gut tube will subdivide into the celiac, superior mesenteric, and inferior mesenteric arteries, supplying ___
the foregut, midgut and hindgut.
Blood Supply to Regions of the Gut Tube
→ identify
Foregut
Region of gut tube extending posteriorly from oral cavity
→ respiratory diverticulum buds off from it, marking eventual location of ____ and ___
esophagus and larynx
Foregut
Region of gut tube extending posteriorly from oral cavity
→ ____ buds off from it, marking eventual location of esophagus and larynx
respiratory diverticulum
Foregut will become ___ (6)
- esophagus
- stomach
- proximal duodenum
- liver
- gallbladder
- pancreas, and spleen
→ receiving blood from branches of celiac trunk
Foregut
→ identify
2 steps in the process of foregut development
- Separation of the esophagus from the larynx and trachea
- Stomach dilation and rotation
Events in Foregut Development
Process:
- Separation of the esophagus from the larynx and trachea
- Stomach dilation and rotation
→ Continued development of the foregut with (2 events)
- Separation of the esophagus from the larynx and trachea
- Stomach dilation and rotation
Tracheoesophageal Septum
=> The development of ____ , that meets on the midline, causes the inferior extension of the respiratory diverticulum and its separation from the foregut.
tracheoesophageal ridges
Tracheoesophageal Septum
=> The development of tracheoesophageal ridges , that meets on the midline, causes the inferior extension of the respiratory diverticulum and its separation from ___
the foregut.
Tracheoesophageal Septum
=> The development of tracheoesophageal ridges , that meets on the midline, causes the inferior extension of ___ and its separation from the foregut.
the respiratory diverticulum
Development of the Hepatic Diverticulum - Foregut Development
During the 3rd week, ___ extends off foregut and grows into mesoderm of ventral mesentery and septum transversum
→ it will form the liver
the hepatic diverticulum (liver bud)
Development of the Hepatic Diverticulum - Foregut Development
During the 3rd week, the hepatic diverticulum (liver bud) extends off foregut and grows into mesoderm of ventral mesentery and septum transversum
→ it will form the ____
liver
Development of the Hepatic Diverticulum - Foregut Development
_____, which connects liver and foregut, is remnant of hepatic diverticulum
Common bile duct
Development of the Hepatic Diverticulum - Foregut Development
Common bile duct, which connects liver and foregut, is remnant of ___
hepatic diverticulum
Development of the Hepatic Diverticulum - Foregut Development -
→ identify
Gallbladder Development - Foregut Development
Develops as a secondary out-pouching from the hepatic diverticulum that grows into ____
Develops as a secondary out-pouching from the hepatic diverticulum that grows into ventral mesentery
Gallbladder Development - Foregut Development
Develops as a secondary out-pouching from ____ that grows into ventral mesentery
the hepatic diverticulum
Gallbladder Development - Foregut Development
Gallbladder develops as a secondary out-pouching from the hepatic diverticulum that grows into ventral mesentery
→ Its connection to hepatic diverticulum will become ____
cystic duct
Gallbladder Development - Foregut Development
→ identify
Ventral and Dorsal Pancreatic Bud - Foregut Development
develops another outgrowth of hepatic diverticulum; it will become uncinate process and part of pancreatic head
Ventral and Dorsal Pancreatic Bud - Foregut Development
Ventral pancreatic bud develops another outgrowth of hepatic diverticulum
→ it will become ____ and ____
uncinate process and part of pancreatic head
Ventral and Dorsal Pancreatic Bud - Foregut Development
____ develops another outgrowth of hepatic diverticulum
→ it will become uncinate process and part of pancreatic head
Ventral pancreatic bud
Ventral and Dorsal Pancreatic Bud - Foregut Development
Separate dorsal pancreatic bud extends separately from nearby gut tube inferior to stomach
→ it will form _____ (3)
body, tail, and part of pancreatic head
Ventral and Dorsal Pancreatic Bud - Foregut Development
→ identify
Fusion of the Pancreatic Buds → ____
form a single pancreas
Fusion of the Pancreatic Buds
Rotation of stomach brings common bile duct and ventral pancreas posterior to duodenum; pancreatic buds fuse to form a single pancreas
→ Thereafter, the duodenum typically receives (1)___ from ventral pancreas and (2)_____ from dorsal pancreas
→ within pancreas, these ducts interconnect
- a main pancreatic duct
- accessory pancreatic duct
Early Development of Foregut Organs
Organs develop within folds of peritoneum
→ Foregut is suspended from posterior body wall by ____
a dorsal mesentery (also called the mesogastrium)
Early Development of Foregut Organs
Organs develop within folds of peritoneum
→ Foregut is suspended from posterior body wall by a dorsal mesentery (also called the mesogastrium)
→ Liver grows within ___ and ____
the ventral mesentery and septum transversum
Early Development of Foregut Organs
Organs develop within folds of peritoneum
→ Gallbladder and ventral pancreatic bud also developing in ____
ventral mesentery
Early Development of Foregut Organs
Organs develop within folds of peritoneum
→ Dorsal pancreatic bud and spleen will develop in ____
dorsal mesentery
Early Development of Foregut Organs
Organs develop within ____
folds of peritoneum
Development of the Lesser Omentum
Liver grows and remains connected to body wall by ventral mesentery, which will eventually remain as ____
falciform ligament
Development of the Lesser Omentum
Liver grows and remains connected to body wall by ventral mesentery, which will eventually remain as falciform ligament
→ Liver begins to fill ____ and pulls on region of ventral mesentery connecting it to stomach
right side of abdominal cavity
Development of the Lesser Omentum
Liver grows and remains connected to body wall by ventral mesentery, which will eventually remain as falciform ligament
→ Liver begins to fill right side of abdominal cavity and pulls on region of ventral mesentery connecting it to stomach
→ Connection between foregut and liver will become____
lesser omentum
Development of the Lesser Omentum
Liver grows and remains connected to body wall by ventral mesentery, which will eventually remain as falciform ligament
→ Liver begins to fill right side of abdominal cavity and pulls on region of ventral mesentery connecting it to stomach
→ Connection between___ and ___ will become lesser omentum
foregut and liver
Development of the Lesser Omentum
As stomach is rotated, the liver pulls ___ to the left
dorsal mesentery
Development of the Lesser Omentum
As stomach is rotated, the liver pulls dorsal mesentery to the left
→ Since spleen begins developing in this region of dorsal mesentery, fold between two organs is called ____
gastrosplenic ligament
Development of the Lesser Omentum
→ identify
Formation of the Omental Bursa and the Greater Omentum
Continued growth of the liver and movement of the stomach creates a blind sac posterior to the lesser omentum.
→ This space within the peritoneum is called____ and ___
the lesser sac or omental bursa.
Formation of the Omental Bursa and the Greater Omentum
Continued growth of the liver and movement of the stomach creates a blind sac posterior to the lesser omentum.
→ This space within the peritoneum is called the lesser sac or omental bursa.
→ It is in contact with the rest of the peritoneal cavity, the greater sac, through a small passage posterior to the lesser omentum which is called ___
the omental foramen.
Formation of the Omental Bursa and the Greater Omentum
→ The dorsal mesentery just below the gastrosplenic ligament expands tremendously, creating ____
the greater omentum.
→ an apron of mesentery that hangs off of the greater curvature of the stomach
Formation of the Omental Bursa and the Greater Omentum
→ ____ just below the gastrosplenic ligament expands tremendously, creating an apron of mesentery that hangs off of the greater curvature of the stomach, the greater omentum.
→ The space between its folds is part of the lesser sac.
The dorsal mesentery
Fusion of Omentum and Mesenteries
The greater omentum unfurls remarkably.
→ The two folds of the greater omentum fuse, creating a single structure that drapes over ____ and ____ (organs) and decreasing the space within the omental bursa.
the large and small intestines
Fusion of Omentum and Mesenteries
The greater omentum unfurls remarkably.
→ The two folds of the greater omentum fuse, creating a single structure that drapes over the large and small intestinesand decreasing the space within (1)____
→ It also fuses with (2)____ all the way to the posterior body wall.
- the omental bursa.
- the mesentery of the transverse colon
Fusion of Omentum and Mesenteries
→ identify
Pancreas and Spleen Migration
During rotation of the foregut, the pancreas moves (1) ____ (anteriorly/posteriorly) within the dorsal mesentery.
→ This mesentery will lay back and fuse with (2)___ of the posterior body wall.
- posteriorly
- the parietal peritoneum
Pancreas and Spleen Migration
During ___, the pancreas moves posteriorly within the dorsal mesentery.
→ This mesentery will lay back and fuse with the parietal peritoneum of the posterior body wall.
rotation of the foregut
Pancreas and Spleen Migration
The dorsal mesentery from the spleen to the body wall is called ___
the splenorenal ligament.
Pancreas and Spleen Migration
→ identify
Pancreas and Spleen Migration
→ identify
Events in Midgut Development
Midgut begins as U-shaped loop of gut with vitelline duct extending from it to ____
definitive yolk sac
Events in Midgut Development
Midgut begins as U-shaped loop of gut with ____ extending from it to definitive yolk sac
vitelline duct
Events in Midgut Development
Midgut begins as U-shaped loop of gut with vitelline duct extending from it to definitive yolk sac
→ Midgut becoming ____ (6)
- distal duodenum
- jejunum
- ileum
- cecumappendix
- ascending colon, and transverse colon
Events in Midgut Development
Midgut begins as U-shaped loop of gut with vitelline duct extending from it to definitive yolk sac
→ Derivatives of midgut receiving blood from-__
branches of superior mesenteric artery
Events in Midgut Development
Midgut begins as U-shaped loop of gut with vitelline duct extending from it to definitive yolk sac
→ Major occurrences in midgut development are ___ (2)
- Rotation
- Elongation
Rotation of the Midgut
Midgut rotates around___
superior mesenteric artery
Rotation of the Midgut
Midgut rotates around superior mesenteric artery; from the front view, you can see the gut rotating counter-clockwise
→ ____ rotates inferiorly to become distal duodenum, jejunum and part of ileum
Proximal (cephalic) loop
Rotation of the Midgut
Midgut rotates around superior mesenteric artery; from the front view, you can see the gut rotating counter-clockwise
→ ___ rotates superiorly, forming the rest of ileum, cecum, appendix, ascending colon and most of transverse colon
Distal (caudal) loop
Rotation of the Midgut
Midgut rotates around superior mesenteric artery; from the front view, you can see the gut rotating counter-clockwise
→ Distal (caudal) loop rotates superiorly, forming ____ (5)
- the rest of ileum
- cecum
- appendix
- ascending colon
- most of transverse colon
Rotation of the Midgut
Midgut rotates around superior mesenteric artery; from the front view, you can see the gut rotating counter-clockwise
→ Proximal (cephalic) loop rotates inferiorly to become ___ (3)
- distal duodenum
- jejunum
- part of ileum
Return of the Midgut to the Abdomen
Midgut structures continue rotating and return to abdomen, jejunum positioned primarily on (!)___
→ other midgut structures laid down progressively more towards (2)___
- left
- the right
Return of the Midgut to the Abdomen
Midgut structures continue rotating and return to abdomen, jejunum positioned primarily on left and other midgut structures laid down progressively more towards the right
→ Typically, cecum comes to rest in ___ (which quadrant of the abdomen)
the lower right of the abdomen
___ buds off the cecum and elongates as it returns to the right side of the abdomen.
The vermiform appendix
(Because the appendix forms as the cecum returns to the abdomen, it may be located in several locations.)
Portions of Midgut Become Retroperitoneal
As gut tube takes final position, mesenteries of several regions pushed against posterior body wall and partially fuse with it
→ Theses regions henceforth called (1)____, distinguishing them from those that maintain distinct mesentery, (2)____; and those that never had a mesentery, (3)____
- secondarily retroperitoneal
- intraperitoneal
- (primarily) retroperitoneal
The vitelline duct extends from the ileum but normally disappears.
→ Sometimes a remnant exists as _____
an ileal (Meckel’s) diverticulum
→ a blind pouch
Hindgut forms remainder of gastrointestinal tract; great deal of overlap between its development and ____
growth of urogenital system
Hindgut become ___
- descending colon
- sigmoid colon
- rectum
Derivatives of HINDGUT receives blood from ___
branches of inferior mesenteric artery
Cloaca and Urorectal Septum
The gastrointestinal, urinary, and reproductive systems meet in ____.
a common compartment called the cloaca
Cloaca and Urorectal Septum
The gastrointestinal, urinary, and reproductive systems meet in a common compartment called the cloaca.
→ It is separated from the amniotic cavity by a thin wall of ectoderm and endoderm
→ What is this wall called?
the cloacal membrane.
Cloaca and Urorectal Septum
The cloaca is divided into anterior and posterior compartments by mesoderm between ____ and ____
the vitelline duct and allantois that “descends”
Cloaca and Urorectal Septum
The cloaca is divided into anterior and posterior compartments by mesoderm between the vitelline duct and allantois that “descends”
→ This mesoderm pinches the cloaca from each side, creating ____
a urorectal septum.
Cloaca and Urorectal Septum
→ identify
Urogenital Sinus and Rectum
The cloaca is divided into anterior and posterior compartments by mesoderm between the vitelline duct and allantois that “descends”
→ Anterior compartment is (1)____
→ will receive products from (2)____ and ___
- urogenital sinus
- urinary/renal and reproductive systems
Urogenital Sinus and Rectum
The cloaca is divided into anterior and posterior compartments by mesoderm between the vitelline duct and allantois that “descends”
→ Posterior compartment is ____
rectum, the final section of hindgut
Urogenital Sinus and Rectum
The cloaca is divided into anterior and posterior compartments by mesoderm between the vitelline duct and allantois that “descends”
Urorectal septum meets outside of body at ____
perineal body
→ an important connective tissue structure of urogenital triangle
Urogenital Sinus and Rectum
→ identify
Anal Development
Rectum covered by____
anal membrane
Anal Development
Rectum covered by anal membrane
→ ectoderm in area invaginates to form ___ that meets rectum and connects to it as membrane ruptures
anal pit
Anal Development
___ inside anal canal marks point where ectoderm of anus and endoderm of rectum meet
Pectinate line
Anal Development
The role of Pectinate line
It is inside anal canal
→ marks point where ectoderm of anus and endoderm of rectum meet
Anal Development
Division is mirrored by venous drainage of anus and rectum
→ portal system drains blood above (1)___ and (2)____ below
- pectinate line
- inferior vena cava system
Anal Development
→ identify
