Embryology - Development Of The Gi Tract

Front 1

The gut tube forms from

Back 1

the yolk sac

Front 2

The epithelial lining of the GI tract is all derived from

Back 2

endoderm

Front 3

The parenchyma of the glands associated with the digestive tract are derived from

Back 3

endoderm

Front 4

The liver and pancreas are derived from

Back 4

endoderm

Front 5

Connective tissue and muscle of the GI tract are derived from

Back 5

splanchnic mesoderm
aka visceral mesoderm

Front 6

The lamina propria of the GI tract is derived from

Back 6

splanchnic mesoderm
aka visceral mesoderm

Front 7

The muscularis mucosae and submucosa of the GI tract are derived from

Back 7

splanchnic mesoderm
aka visceral mesoderm

Front 8

The muscularis externa of the GI tract is derived from

Back 8

splanchnic mesoderm
aka visceral mesoderm

Front 9

The adventitia (serosa) of the GI tract is derived from

Back 9

splanchnic mesoderm
aka visceral mesoderm

Front 10

The foregut is the region of the gut from the ___ to the ___

Back 10

from the oropharyngeal membrane to the hepatic diverticulum (liver outgrowth)

Front 11

The foregut receives its arterial blood supply from the

Back 11

celiac artery

Front 12

The pharynx forms from the

a. foregut
b. midgut
c. hindgut

Back 12

foregut

Front 13

The respiratory tract forms from the
a. foregut
b. midgut
c. hindgut

Back 13

foregut

Front 14

The esophagus forms from the

a. foregut
b. midgut
c. hindgut

Back 14

foregut

Front 15

The stomach forms from the

a. foregut
b. midgut
c. hindgut

Back 15

foregut

Front 16

The proximal half of the duodenum forms from the

a. foregut
b. midgut
c. hindgut

Back 16

foregut

Front 17

The liver forms from the

a. foregut
b. midgut
c. hindgut

Back 17

foregut

Front 18

The biliary apparatus forms from the

a. foregut
b. midgut
c. hindgut

Back 18

foregut

Front 19

The pancreas forms from the

a. foregut
b. midgut
c. hindgut

Back 19

foregut

Front 20

The midgut portion of the gut is the portion from the ____ to the ____

Back 20

from the hepatic diverticulum (liver outgrowth) to the junction between the right 2/3 and left 1/3 of the transverse colon

Front 21

The midgut receives its arterial blood supply from the

Back 21

superior mesenteric artery

Front 22

The distal half of the duodenum forms from the

a. foregut
b. midgut
c. hindgut

Back 22

midgut

Front 23

The jejunum forms from the

a. foregut
b. midgut
c. hindgut

Back 23

midgut

Front 24

The ileum forms from the

a. foregut
b. midgut
c. hindgut

Back 24

midgut

Front 25

The ascending colon forms from the

a. foregut
b. midgut
c. hindgut

Back 25

midgut

Front 26

The proximal 2/3 of the transverse colon forms from the

a. foregut
b. midgut
c. hindgut

Back 26

midgut

Front 27

The yolk stalk forms from the

a. foregut
b. midgut
c. hindgut

Back 27

midgut

Front 28

The cecum forms from the

a. foregut
b. midgut
c. hindgut

Back 28

midgut

Front 29

The appendix forms from the

a. foregut
b. midgut
c. hindgut

Back 29

midgut

Front 30

The hindgut portion of the gut tube is the portion from the ___ to the ____

Back 30

from the left 1/3 transverse colon to the cloacal membrane

Front 31

The hindgut receives its arterial blood supply from the

Back 31

inferior mesenteric artery (and its branches)

Front 32

The distal 1/3 of the transverse colon forms from the

a. foregut
b. midgut
c. hindgut

Back 32

hindgut

Front 33

The descending colon forms from the

a. foregut
b. midgut
c. hindgut

Back 33

hindgut

Front 34

The sigmoid colon forms from the

a. foregut
b. midgut
c. hindgut

Back 34

hindgut

Front 35

The rectum forms from the

a. foregut
b. midgut
c. hindgut

Back 35

hindgut

Front 36

The upper 2/3 of the anal canal is formed from the

a. foregut
b. midgut
c. hindgut

Back 36

hindgut

Front 37

The epithelium of the urinary bladder is formed from the

a. foregut
b. midgut
c. hindgut

Back 37

hindgut

Front 38

The majority of the urethra is formed from the

a. foregut
b. midgut
c. hindgut

Back 38

hindgut

Front 39

The anterior 2/3 of the oral cavity is formed from the ____ which is _____

Back 39

from the stomodeum which is surface ectoderm

Front 40

The posterior 1/3 of the oral cavity is formed from the ____ which is _____

Back 40

from the foregut which is endoderm

Front 41

The anterior 2/3 and posterior 1/3 of the oral cavity are separated by the

Back 41

oropharyngeal membrane

Front 42

The respiratory tract forms from an outgrowth of the foregut called the

Back 42

respiratory diverticulum

Front 43

The process of forming the respiratory tract occurs through the formation of _______ which will fuse and then ultimately divide the foregut into 2 parallel tubes

Back 43

tracheoesophageal folds

Front 44

The foregut is divided into 2 parallel tubes with the division of the tracheoesophageal septum.

The dorsal tube is the ____
The ventral tube is the _____

Back 44

dorsal tube - esophagus

ventral tube - laryngotracheal tube

Front 45

Esophageal atresia results when the tracheoesophageal septum is

Back 45

deviated posteriorly

Front 46

Incomplete separation of the esophagus from the laryngotracheal tube results in a

Back 46

concurrent tracheoesophageal fistula

Front 47

A pregnant woman exhibits polyhydramnios and absence of stomach gas on ultrasound. Once born, the baby has copious, fine white frothy bubbles of mucus from the nose and mouth. The condition this describes is

Back 47

esophageal atresia

Front 48

A newborn baby exhibits coughing and choking. There is also abdominal distension secondary to collection of air in the stomach. The condition this describes is

Back 48

tracheoesophageal fistula

Front 49

Narrowing of the esophageal lumen is termed....

This occurs due to

Back 49

esophageal stenosis

occurs due to incomplete recanalization of the gut tube

Front 50

Esophageal stenosis usually occurs in what portion of the esophagus?

Back 50

distal 1/3

Front 51

A patient has difficulty swallowing and reports feeling like their is blockage in his throat. This is likely what condition

Back 51

esophageal stenosis

Front 52

Recanalization of the gut tube usually occurs in the ___ week of development

Back 52

8th

Front 53

The stomach rotates __ degrees in which direction?

Back 53

90 degrees clockwise

Front 54

Rotation of the stomach moves the right portion ____ and the left portion ____

(dorsal vs ventral)

Back 54

right - dorsal
left - ventral

Front 55

The vagus nerves are originally left and right structures. They become dorsal and ventral structures because of what

Back 55

rotation of the stomach 90 degrees clockwise

Front 56

The left side of the stomach is the ____ curvature

Back 56

greater curvature


*because the dorsal portion of the foregut that forms part of the stomach is larger than the ventral part and with rotation of the stomach the dorsal part moves to the left

Front 57

The right side of the stomach is the ____ curvature

Back 57

lesser curvature

*because the ventral portion of the foregut that forms part of the stomach is smaller than the dorsall part and with rotation of the stomach the ventral part moves to the right

Front 58

The stomach is a little tilted with rotation. The cranial portion tilts ___ and ___

(left/right)
(superior/inferior)

Back 58

left and inferior

Front 59

The stomach is a little tilted with rotation. The caudal portion moves ___ and ___

(left/right)
(superior/inferior)

Back 59

right and superior

Front 60

The most caudal part of the stomach is the ___ which is continuous with the duodenum

Back 60

pylorus

Front 61

Pyloric stenosis is due to

Back 61

an overgrowth of the sphincter muscle in the pyloric region

Front 62

A newborn baby in her first 1-2 weeks of life exhibits forceful, projectile vomiting. This baby has what condition?

Back 62

pyloric stenosis

Front 63

The dorsal mesogastrium is carried to the ____ as the stomach rotates (left or right?)

Back 63

left

Front 64

The hepatic diverticulum grows out of the

Back 64

ventral foregut

Front 65

Where the liver touches the diaphragm is called the...

Back 65

bare area

Front 66

The whole liver is covered by ____ except the bare area.

Back 66

ventral mesentery

Front 67

What 2 things are formed by the hepatic diverticulum?

Back 67

liver
hepatic duct

Front 68

What 2 things are formed by the cystic diverticulum?

Back 68

gallbladder
cystic duct

Front 69

The stalk that connects the hepatic duct and cystic duct to the duodenum becomes the

Back 69

common bile duct

Front 70

The pancreas forms from

Back 70

ventral pancreatic bud off the hepatic diverticulum

and

dorsal pancreatic bud off the dorsal side of the foregut

Front 71

The pancreas is ____ lined

Back 71

endoderm

Front 72

The ventral pancreatic bud forms what 3 things

Back 72

uncinate process
main pancreatic duct
inferior portion of the head of the pancreas

Front 73

The ventral pancreatic bud fuses with the dorsal pancreatic bud when ....

Back 73

the stomach rotates 90 degrees, carrying the ventral pancreatic bud dorsally

Front 74

The dorsal pancreatic bud forms what 3 to 4 things?

Back 74

superior portion of the head of the pancreas
body of pancreas
tail of pancreas
accessory bile duct (not present in everyone)

Front 75

The portion of the duodenum that is proximal to the bile duct is formed from

a. foregut
b. midgut
c. hindgut

so it gets its arterial blood supply from...

Back 75

foregut

celiac artery

Front 76

The portion of the duodenum that is distal to the bile duct is formed from

a. foregut
b. midgut
c. hindgut

so its arterial blood supply is from...

Back 76

midgut

superior mesenteric artery

Front 77

Incomplete recanalization of the duodenum leads to

Back 77

duodenal stenosis

Front 78

A patient reports vomiting, gastroesophageal reflux, and has peptic ulcers which you suspect are due to retention of pancreatic enzymes in the stomach. You think this patient has

Back 78

duodenal stenosis

Front 79

If the duodenum fails to recanalize at all then this is called

Back 79

duodenal atresia

Front 80

Bile containing vomitus, a distended stomach, and maternal polyhydramnios are characteristic of

Back 80

duodenal atresia distal to the hepatic duct


**if it is not distal to the hepatic duct then the vomit will not contain bile

Front 81

The midgut is connected to the yolk sac by the

Back 81

vitelline duct (aka yolk stalk)

Front 82

Which portion of the gut tube forms a loop?

a. foregut
b. midgut
c. hindgut

Back 82

the midgut

-called the "midgut loop"

Front 83

The midgut loop forms 2 limbs. The cranial limb forms the
(2 things)

Back 83

jejunum and proximal ileum

Front 84

The midgut loop forms 2 limbs. The caudal limb forms the
(5 things)

Back 84

distal ileum
cecum
appendix
ascending colon
proximal 2/3 of transverse colon

Front 85

A physiologic hernia is normal and occurs around ___ weeks

Back 85

6 weeks

Front 86

The midgut grows outside of the embryo into the umbilical cord and this is called a

Back 86

physiologic hernia

Front 87

When the midgut herniates into the umbilical cord, it ...

Back 87

rotates 90 degrees counterclockwise

Front 88

When the midgut rotates 90 degrees counterclockwise to herniate into the umbilical cord, the cranial limb moves to the ___ and the caudal limb moves to the ___
(left vs right)

Back 88

cranial limb to the right
caudal limb to the left

Front 89

The midgut should return to the abdominal cavity at ___ weeks of development after its physiologic hernia into the umbilical cord.

Back 89

10 weeks

Front 90

To return to the abdominal cavity after physiologic hernia into the umbilical cord, the midgut will

Back 90

rotate 180 degrees counterclockwise

Front 91

When the midgut rotates 180 degrees counterclockwise to return back to the abdominal cavity after herniating into the umblical cord, the cranial limb of the loop ends up on the ___ side of the fetus and the caudal limb ends up on the ___ side of the fetus.

Back 91

cranial limb ends up on the left side of the fetus
caudal limb ends up on the right side of the fetus

Front 92

In total, the midgut rotates ___ degrees ____

Back 92

270 degrees counterclockwise

(herniation and return to abdominal cavity)

Front 93

The cecum is originally in the...

It ends up in the...

why does it move?

Back 93

right upper quadrant of the abdomen (below the right lobe of the liver)

it ends up in the right lower quadrant or right iliac fossa

it moves when the midgut returns to the abdominal cavity

Front 94

The appendix forms as a

Back 94

diverticulum of the cecum

Front 95

The appendix forms during the

Back 95

descent of the cecum from the RUQ to the RLQ

Front 96

What condition prevents the normal fixation of the intestines?

Back 96

malrotation of the midgut

Front 97

What is a volvulus?
What can it be due to?

Back 97

twisting of the intestines

can be due to malrotation of the midgut which prevents normal fixation of the intestines so that they are freer to twist

Front 98

Twisting of the intestines can cause what 4 things

Back 98

strangulation
obstruction
necrosis
death

Front 99

If the midgut loop does not return to the abdominal cavity, what is formed

Back 99

omphalocoel

Front 100

A baby is born and the intestines are found covered with amnion in the umbilical cord. This is

Back 100

an omphalocoel

Front 101

There is protrusion of viscera directly into the amniotic cavity because lateral body walls do not fuse correctly. This is called

Back 101

gastroschisis

Front 102

Gastroschisis usually occurs where?

Back 102

on the right side of the umbilicus

(always lateral to the umbilicus)

Front 103

Viscera which are protruding and are NOT covered in amnion but are exposed directly to amniotic fluid are from (a)

a. omphalocoel
b. gastroschisis
c. nonrotation of the midgut
d. malrotation of the midgut

Back 103

gastroschisis

Front 104

What is the most common congenital anomaly of the GI tract?

Back 104

Ileal (Meckel's) Diverticulum

Front 105

What are the 3 two's of Ileal (Meckel's) diverticulum?

Back 105

occur 2 cm from the ileocecal junction
occur in 2% of the population
are 2 times more frequent in males than females

Front 106

Ileal (Meckel's) Diverticulum is due to

Back 106

incomplete obliteration of the yolk stalk (aka vitelline duct)

Front 107

If the vitelline duct is not completely pinched off with body folding, and a remnant of it remains attached to the ventral body wall, the patient will have a

Back 107

vitelline ligament

Front 108

If a remnant of the vitelline duct is directly connected to the umbilicus it is called a ...

it occurs because the vitelline duct is not completely pinched off during body folding

Back 108

vitelline fistula

Front 109

The terminal end of the hindgut is called the

Back 109

cloaca

Front 110

The 2 portions that the cloaca is partitioned into are the

Back 110

urogenital sinus ventrally and
rectum dorsally

Front 111

The urogenital sinus gives rise to what 2 to 3 things?

Back 111

bladder
urethra (most of it)

*part of vagina in females

Front 112

The cloaca terminates at the

Back 112

cloacal membrane

Front 113

The cloacal membrane is covered by ____ externally and ____ internally

Back 113

surface ectoderm externally
hindgut endoderm internally

Front 114

The urorectal septum is a ______ that forms and puts pressure on the cloaca causing it to partition into the urogenital sinus and rectum.

Back 114

wedge of mesoderm

Front 115

What causes the cloaca to become partitioned into the urogenital sinus and rectum?

Back 115

a wedge of mesoderm called the urorectal septum forms and puts pressure on it

Front 116

The cloacal membrane forms what 2 things

Back 116

urogenital membrane covering the urogenital sinus
anal membrane covering the anus

Front 117

The upper 2/3 of the anal canal forms from

a. foregut
b. midgut
c. hindgut

so it is ...

Back 117

hindgut

so it is endoderm

Front 118

The distal 1/3 of the anal canal forms from

Back 118

surface ectoderm of the anal membrane

Front 119

If the partitioning of the cloaca is incomplete, this is a(n)

Back 119

urorectal fistula

Front 120

An abnormal connection of the rectum to either the urethra or bladder is called a(n)

Back 120

urorectal fistula

Front 121

If the anal membrane fails to break down, this is called a(n)

Back 121

imperforate anus

Front 122

If there is not a direct connection between the anal canal and rectum it is called a(n)

Back 122

imperforate anus

Front 123

Hirschsprung's disease is due to a failure of...

Back 123

neural crest cells migrating to the walls of intestines

Front 124

An absence of peristalsis in regions of the intestines can lead to bowel obstruction and characterizes what condition

Back 124

Hirschsprung's disease

Front 125

True or False: Hirschsprung's disease affects the entire length of the intestines rather than separate regions.

Back 125

False.

it is not continuous for the entire length of the intestines but occurs in regions

Front 126

Ligaments and membranes associated with the spleen form from the

Back 126

dorsal mesentery (dorsal mesogastrium)

Front 127

The greater omentum forms from the

Back 127

dorsal mesentery (dorsal mesogastrium)

Front 128

The mesentery of the small intestine forms from the

Back 128

dorsal mesentery (dorsal mesogastrium)

Front 129

The mesoappendix forms from the

Back 129

dorsal mesentery (dorsal mesogastrium)

Front 130

The transverse mesocolon forms from the

Back 130

dorsal mesentery (dorsal mesogastrium)

Front 131

The sigmoid mesocolon forms from the

Back 131

dorsal mesentery (dorsal mesogastrium)

Front 132

All the mesenteries of the liver form from the

Back 132

ventral mesentery (ventral mesogastrium)

Front 133

The lesser omentum forms from the

Back 133

ventral mesentery (ventral mesogastrium)

Front 134

The hepatogastric ligament forms from the

Back 134

ventral mesentery (ventral mesogastrium)

Front 135

The hepatoduodenal ligament forms from the

Back 135

ventral mesentery (ventral mesogastrium)

Front 136

The falciform ligament forms from the

Back 136

ventral mesentery (ventral mesogastrium)

Front 137

The lesser omentum forms between the ___ and ____

Back 137

stomach and liver

Front 138

The falciform ligament forms between the ___ and ___

Back 138

liver and ventral body wall

Front 139

GI organs which are suspended by a mesentery are called

Back 139

intraperitoneal

Front 140

GI organs which were once suspended by a mesentery but became pinned behind a mesentery are called

Back 140

secondarily retroperitoneal

Front 141

GI organs which were never suspended by a mesentery and are pinned behind mesentery are called

Back 141

retroperitoneal

Front 142

The liver is

a. intraperitoneal
b. retroperitoneal
c. secondarily retroperitoneal

Back 142

intraperitoneal

Front 143

The abdominal esophagus is

a. intraperitoneal
b. retroperitoneal
c. secondarily retroperitoneal

Back 143

intraperitoneal

Front 144

The gallbladder and bile duct are

a. intraperitoneal
b. retroperitoneal
c. secondarily retroperitoneal

Back 144

intraperitoneal

Front 145

The jejunum and ileum are

a. intraperitoneal
b. retroperitoneal
c. secondarily retroperitoneal

Back 145

intraperitoneal

Front 146

The transverse colon is

a. intraperitoneal
b. retroperitoneal
c. secondarily retroperitoneal

Back 146

intraperitoneal

Front 147

The stomach is

a. intraperitoneal
b. retroperitoneal
c. secondarily retroperitoneal

Back 147

intraperitoneal

Front 148

The cecum and appendix are

a. intraperitoneal
b. retroperitoneal
c. secondarily retroperitoneal

Back 148

intraperitoneal

Front 149

The sigmoid colon is

a. intraperitoneal
b. retroperitoneal
c. secondarily retroperitoneal

Back 149

intraperitoneal

Front 150

The ascending colon is

a. intraperitoneal
b. retroperitoneal
c. secondarily retroperitoneal

Back 150

secondarily retroperitoneal

Front 151

The descending colon is

a. intraperitoneal
b. retroperitoneal
c. secondarily retroperitoneal

Back 151

secondarily retroperitoneal

Front 152

The pancreas is

a. intraperitoneal
b. retroperitoneal
c. secondarily retroperitoneal

Back 152

secondarily retroperitoneal

Front 153

The duodenum is

a. intraperitoneal
b. retroperitoneal
c. secondarily retroperitoneal

Back 153

secondarily retroperitoneal

Front 154

The thoracic esophagus is

a. intraperitoneal
b. retroperitoneal
c. secondarily retroperitoneal

Back 154

retroperitoneal

Front 155

The rectum is

a. intraperitoneal
b. retroperitoneal
c. secondarily retroperitoneal

Back 155

retroperitoneal

Front 156

The formation of the GI tract is pretty much all done by ___ weeks.

Back 156

12 weeks