Development of Digestive System Flashcards
1
Q
Gastrulation occurs in week _____ and is the process in which we form what 3 germ layers?
A
3
Ectoderm, mesoderm, and endoderm
2
Q
T/F: All 3 germ layers contribute to formation of the GI tract
A
True
3
Q
How does endoderm contribute to the GI tract?
A
It gives rise to the epithelial lining & glands of the GI tract
4
Q
The foregut forms from the head or tail fold?
A
head
5
Q
The hindgut forms from the head or tail fold?
A
tail
6
Q
What structure is a temporary connection between the midgut and yolk sac?
A
Vitelline duct
7
Q
During ______ folding, yolk sac endoderm is incorporated as embryonic midgut
A
lateral
8
Q
The primitive gut tube extends cranially all the way to the _______ membrane
A
oropharyngeal
9
Q
The primitive gut tube extends caudally all the way to the ______ membrane
A
cloacal
10
Q
The oropharyngeal membrane ruptures in what week?
A
week 4
11
Q
The cloacal membrane is formed by the pinching together of what two -derm layers?
A
ectoderm
endoderm
12
Q
The cloacal membrane ruptures in what week?
A
week 8
13
Q
Mesoderm and endoderm both contribute to parts of the ____ of the GI tract
A
walls
14
Q
Splanchnic mesoderm forms what in relation to the GI tract?
A
smooth m. & CT of GI tract
15
Q
T/F: All inner epithelial lining of anything coming from the digestive tract is derived from mesoderm.
A
False. It is all derived from endoderm
16
Q
Peritoneum & Mesenteries are derived from what germ layer?
A
Mesoderm
17
Q
Parietal peritoneum is derived from what type of mesoderm?
A
somatic
18
Q
Visceral peritoneum, dorsal mesentery, and ventral mesentery are derived from what mesoderm?
A
splanchnic
19
Q
Thin serous membrane lining the organs is termed what?
A
visceral peritoneum
20
Q
A double-layer of peritoneum that suspends an organ from the body wall is termed what?
A
Mesentery
21
Q
The _____ mesentery exists throughout the whole abdominal cavity, while the ______ mesentery disappears in the lower abdomen
A
dorsal
ventral
22
Q
T/F: Mesentery can serve as a route of travel (conduit) for blood vessels, lymphatics, and nerves to travel from the body wall to the organs and from organ to organ.
A
True
23
Q
______ body folding creates Mesenteries by stretching out splanchnic mesoderm
A
Lateral
24
Q
The ventral mesentery is resorbed inferior to the ________
A
foregut
25
Mesogastrium is the mesentery of the ______
stomach
26
The ______ mesogastrium is split into two pieces by the liver
ventral
27
The ventral mesogastrium is split by the outgrowth of what structure?
liver
28
In gross anatomy, the ventral mesogastrium between the liver and ant. body wall is described as what?
falciform ligament
29
Any mesentery at the level of the stomach is called what?
mesogastrium
30
In gross anatomy, the ventral mesogastrium between the liver and the stomach is termed ____ ___. This structure has two ligaments associated with it, what are they?
Lesser omentum
| hepatogastric & hepatoduodenal ligaments
31
In gross anatomy, the dorsal mesogastrium is termed what?
Greater omentum
32
The dorsal mesogastrium of the duodenum is called what?
Mesoduodenum
33
The dorsal mesogastrium of the small intestines is called what?
Mesentery proper
34
The dorsal mesogastrium of the large intestine (aka the colon) is termed what?
Mesocolon
35
The ectoderm contribution to the GI tract is in the form of what?
Neural Crest Cells
36
From weeks 5 to 7 neural crest cells will migrate away from neural tube and enter the wall of the digestive tract and will form the _____ _____ system
enteric nervous
37
T/F: The enteric nervous system functions autonomously
True
38
The foregut extends from the _____ down the stomach until halfway across the _____
esophagus
| duodenum
39
The midgut extends from halfway across the _____ to 2/3 across the _____ ____
duodenum
| Transverse colon
40
The hindgut extends from 1/3 of the _____ _____ to the _____
Transverse colon
| anus
41
Foregut is supplied by what artery?
Celiac trunk
42
Midgut is supplied by what artery?
Superior Mesenteric a
43
Hindgut is supplied by what artery?
Inferior Mesenteric a
44
All branches of the '-gut' arterial supply are derived from what artery?
abdominal aorta
45
From superior to inferior what are the main branches of the abdominal aorta?
Celiac Trunk a
Superior Mesenteric a
Inferior Mesenteric a
46
What is the main artery that supplies the pharynx?
Pharyngeal arch aa.
47
What six structures are derived from the Foregut?
```
Pharynx
Lower Respiratory system
Esophagus
Stomach
Proximal 1/2 of duodenum
Associated organs (liver, gall bladder, biliary system, pancreas)
```
48
In the 4th week, we see a outgrowth of endoderm from the esophagus ventrally that is called what?
Respiratory diverticulum (Tracheo-bronchial diverticulum or lung bud)
49
The respiratory diverticulum will form what structures in the adult human?
Trachea
Respiratory tree
lungs
50
What week does the stomach develop?
Week 4
51
The _____ side of the stomach expands faster and forms the ____ _____
dorsal
| greater curvature
52
The ____ side of the stomach expands slower and forms the ____ ____
ventral
| lesser curvature
53
T/F: While looking from the superior view during embryologic development the stomach undergoes 90 degree counterclockwise rotation
False: Stomach undergoes 90 degree clockwise rotation
54
The greater curvature of the stomach is on the _____ side of the body, the lesser curvature of the stomach is on the _____ of the body
left
| right
55
The right vagus n. supplies ____ stomach
dorsal
56
The left vagus n. supplies the ____ stomach
ventral
57
The ventral stomach is supplied by the ___ ____ nerve
left vagus
58
The dorsal stomach is supplied by the ____ ___ nerve
right vagus
59
What day does rotation of the stomach occur?
Day 35
60
Why does the stomach shift to the left?
Because the dorsal side expands faster and causes the shift
61
What structure forms between 2 leaves of dorsal mesogastrium in week 5?
Spleen
62
As the stomach rotates the dorsal mesogastrium is carried to the ____, while the ventral mesogastrium is carried to the ____
left
| right
63
This structure is an enlargement of the peritoneum to a sizable recess between the stomach and post. abdominal wall
omental bursa (lesser sac)
64
What causes the omental bursa?
stomach rotation to the left
65
T/F: Greater Omentum can shift and seal off wounds in the abdominal cavity to prevent infections from spreading
True
66
This structure forms a C-shaped loop distal to stomach
Duodenum
67
The Foregut- Midgut split occurs where?
Just distal to opening for pancreatic & common bile ducts (major duodenal papilla)
68
The duodenum twists in a ____ direction, along with the stomach
clockwise (to the right)
69
T/F: The proximal duodenum and pancreas become pressed against the posterior wall
False: The distal duodenum and pancreas become pressed against the post. wall
70
The duodenum and Pancreas are ______ retroperitoneal
secondarily
71
The kidneys are ______ retroperitoneal
primarily
72
Structures located retroperitoneal are sandwiched between _____ and ____
dorsal body wall
| parietal peritoneum
73
What structure emerges ventrally from endoderm of distal foregut during the 4th week of embryological development
Hepatic diverticulum
74
The Hepatic Diverticulum gives rise to what?
Liver, gall bladder, and bile ducts
75
The Liver, gall bladder, and bile ducts are derived from what embryological structure?
Hepatic diverticulum
76
The embryological origin of the diaphragm is termed what?
Septum Transversum
77
What develops from the distal foregut as two endodermal buds?
Pancreas
78
As the duodenum rotates the ____ bud of the pancreas swings with it in a CW direction
ventral
79
The ventral bud of the pancreas becomes the _____ process and the ____ portion of the _____ of the pancreas
uncinate
inferior
head
80
The main pancreatic duct is a fusion of the _____ portion of the dorsal bud duct + ventral bud duct
distal
81
The distal portion of the dorsal bud duct and ventral bud duct fuse to form what?
Main pancreatic duct
82
The Accessory pancreatic duct is derived from what structure?
proximal dorsal bud duct
83
What is the resulting term, if the two portions of the ventral bud of the pancreas don't fuse together prior to rotation, resulting in an obstructive ring around the duodenum
Annular Pancreas
84
What two clinical symptoms would Annular Pancreas result in?
bile stained vomit and whitish gray feces
85
What 7 structures are derived from the Midgut?
```
Distal 1/2 of duodenum
Jejunum
Ileum
Cecum
Appendix
Ascending colon
Proximal 2/3 transverse colon
```
86
As intestines of midgut grow they form a 'U-shaped' loop that extends _______
ventrally
87
Where the cranial (superior) limb of the 'U-shaped' midgut loop meets the caudal (inferior) limb of the loop meet is where we have what structure?
Vitelline (omphaloenteric) duct
88
The cranial limb gives rise to all of what structure?
small intestine (distal duodenum, jejunum, and proximal ileum)
89
The caudal limb gives rise to what structures?
Distal ileum
Cecum+appendix
Ascending colon
Proximal 2/3 transverse colon
90
The vitelline duct comes out right at the _____ level
ileum
91
When does the physiological umbilical herniation occur?
Weeks 6-10
92
Insufficient room in the abdominal cavity leads to temporary herniation of midgut loop into the proximal umbilical cord this is termed what?
Physiological umbilical hernia
93
A persisting umbilical hernia is called what?
Congenital Omphaloceoele
94
A hernia of small intestine and occasionally other abdominal viscera through anterior body wall is termed what?
Gastrochisis
95
T/F: In Gastrochisis the hernia is always lateral to the umbilical cord
True
96
T/F: A long exposure to amniotic fluid will not harm viscera
False
97
The first midgut rotation occurs in what week?
Week 6
98
The week 6 rotation when viewed anteriorly goes in what direction?
90 degrees in a counterclockwise direction
99
During the first midgut rotation the axis of rotation is what structure?
Superior mesenteric artery
100
After the first midgut rotation all of the small intestines will be located on the persons ____ and all the large intestines will be located on the persons _____
right
| left
101
Prior to the first midgut rotation the large intestine is located _____ to the small intestine
inferior
102
At week ____ the intestines can come back in the abdomen
10
103
The second midgut rotation rotates _____ degrees in a _____ direction
180
| counterclockwise
104
In total the midgut loop undergoes _____ degrees of rotation in 2 parts
270
105
As cecum is being dragged down our ascending colon ends up on the _____ and our descending colon ends up on the ____
right
| left
106
As the cecum is being dragged down the ascending colon and descending colon are being pushed to the posterior wall causing these structures to become ______
secondarily retroperitoneal
107
What 5 structures are retroperitoneal?
```
Distal duodenum
Pancreas
Ascending colon
Descending colon
Kidneys
```
108
Which structure(s) are secondarily retroperitoneal?
Distal duodenum
Pancreas
Ascending colon
Descending colon
109
Which structure(s) are primarily retroperitoneal?
Kidneys
110
What 6 structures are intraperitoneal?
```
Stomach
Proximal duodenum
Jejunum
Ileum
Transverse colon
Sigmoid colon
```
111
In cases of non rotation you end up with all of large intestine on the ___ side and all of small intestine are on the ____ side
left
| right
112
In cases of reverse rotation of the midgut, the ___ rotation is normal, but the ___ rotation is reversed
1st
| 2nd
113
In ______ rotation you end up with the midgut and hindgut in normal positions except the _____ is ventral to the transverse cecum instead of behind it
reversed
| duodenum
114
An abnormal rotation that may cause intestinal loop twist around mesenteric attachment site is termed what?
Volvulus
115
A volvulus can result in what?
bowel obstruction, compromised blood flow
116
The abnormal narrowing of a lumen/ orifice is termed what?
stenosis
117
The condition in which a body lumen or orifice is abnormally closed or absent is what?
Atresia
118
An abnormal passageway between two organs/ vessels or between an organ and the external environment is what?
Fistula
119
At week ___ the intestines become occluded by epithelial cells
6
120
The midgut loop should reanalyze by the end of week ___
8
121
The most common GI malformation is what?
Meckel's (ileal) diverticulum
122
A remnant of what structure causes the Meckel's (ileal) diverticulum?
vitelline duct
123
If the vitelline duct fails to degenerate completely it can form what three things?
```
Vitelline ligament (closes off but stays connected)
Vitelline cyst (closes off but fluid is present)
Vitelline fistula ( vitelline duct never closed off)
```
124
What 5 structures are derived from the hindgut?
```
Distal 1/3 transverse colon
Descending colon
Sigmoid colon
Rectum
Superior portion of anal canal
```
125
In week 4 we form a rigid mesoderm termed what?
Urorectal septum
126
A urorectal septum grows _____ toward the cloacal membrane, dividing it into ______ and ____ membranes
inferiorly
urogenital
anal
127
the cloaca is partitioned into the ______ _____ (ventrally) and the ______ _____ (dorsally)
urogenital sinus
| anorectal canal
128
This disease affects variable portions of the bowel where the neural crest cells fail to migrate to form the enteric nervous system
Hirschsprung's Disease
129
Hirschsprung's disease normally affects what portions of the bowel?
distal portions usually sigmoid colon and/ or rectum
130
In Hirschsprung's Disease, aganglionic portion constricts, bowel distends proximal to constriction and results in what symptoms?
severe constipation
| failure to thrive
