Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

GI lectures > development of the foregut > Flashcards

development of the foregut Flashcards

1
Q

where does foregut start and end

A

starts from the distal oesophagus

ends halfway along the duodenum (proximal end)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

where does midgut start and end

A

starts from the distal half of the duodenum

ends at the last 1/3rd of the transverse colon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

where does hindgut start and end

A

starts from distal 1/3rd of the
transverse colon

ends at the upper anal canal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

blood supply of foregut

A

celiac arterty

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

components of foregut (4)

A
  • pharynx
  • oesophagus
  • stomach
  • proximal half of duodenum and the derivative (liver, biliary apparatus & the pancreas)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

blood supply of midgut

A

superior mesenteric artery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

components of midgut

A
  • distal half of the duodenum
  • jejunum
  • ileum
  • caecum
  • appendix
  • ascending colon
  • right 2/3rds of the transverse colon
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

blood supply of hindgut

A

inferior mesenteric artery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

components of hindgut

A
  • left 1/3 of the transverse colon
  • descending colon
  • sigmoid colon
  • rectum
  • anal canal
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is embryonic folding

A

during the 4th week of development the embryo begins to fold and change shape from a flat trilaminar disc into a
cylinder

this process is known as embryonic folding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what are the 2 planes of embryonic folding

A

the horizontal & medial planes
or
longitudinal & transverse folding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

why does embryonic folding occur in 2 planes

A

due to the differing rates of growth of the embryonic structures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what does folding in the horizontal plane result in

A

the formation of the two lateral body folds - transverse

lateral folding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what does folding in the medial plane result in

A

the formation of the cranial & caudal folds - longitudinal

cephalo-caudal folding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

does folding in both planes occur simultaneously or separately

A

simultaneously

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is mainly responsible for the development of the GI tract

A

the endoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what happens as embryonic folding continues

A

the endoderm moves towards the midline and fuses
- incorporating the dorsal part of the yolk sac to form the primitive gut tube

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what is the primitive gut-derived from

A

the endoderm and the visceral mesoderm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what does the endoderm give rise to

A
  1. Epithelial lining of digestive tract
  2. Hepatocytes of the liver
  3. Endocrine and exocrine cells of the pancreas
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what does the visceral mesoderm give rise to

A
  1. Muscle, connective tissue & peritoneal components of the wall of the gut
  2. Connective tissue for the glands
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what does the primitive gut tube differentiate into

A

the foregut, midgut & hindgut

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

where is the foregut

A

on the cranial end of the embryo and is temporarily closed by the oropharyngeal membrane which at the end of the 4th week of development ruptures to form the mouth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

where is the midgut

A

lies between the fore and hindgut
and remains connected to the yolk sac until the 5th week of development

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

where is the hindgut

A

lies at the caudal end of the embryo, it is temporarily closed by the cloacal membrane, which during the 7th week of development, ruptures to
form the anus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
what is the vitelline duct
as embryonic folding continues, the connection to the yolk sac narrows into a stalk called the vitelline duct - an embryonic structure providing communication from the yolk sac to the midgut during fetal development
26
sympathetic innervation of foregut from ANS
greater splanchic nerve (T5-T9)
27
parasympathetic innervation of foregut from ANS
vagus
28
sympathetic innervation of midgut from ANS
lesser splanchnic nerve (T10-T11)
29
parasympathetic innervation of midgut from ANS
vagus
30
sympathetic innervation of hindgut from ANS
least splanchnic nerve (T12 +/- L1) and lumbar splanchnic nerves
31
parasympathetic innervation of hindgut from ANS
pelvic splanchnics
32
where is foregut visceral pain felt
epigastric region
33
where is midgut visceral pain felt
umbilical region
34
where is hindgut visceral pain felt
suprapubic region
35
where does bilaminar disc develop from
the inner cell mass
36
describe gastrulation process (5 steps)
1. primitive streak forms on epiblast 2. epiblast cells migrate to primitive streak and invaginate through it 3. some cells displace the hypoblast and form the endoderm 4. some cells create a new layer between the epiblast and endoderm = mesoderm 5. epiblast = ectoderm
37
what are the 3 germ layers
ectoderm mesoderm endoderm
38
describe muscle of upper 2/3 of oesophagus
striated muscle
39
describe muscle of lower 1/3 of oesophagus
smooth muscle
40
what is upper 2/3 of oesophagus innervated by
vagus nerves
41
what is lower 1/3 of oesophagus innervated by
splanchnic nerves
42
what happens to oesophagus in the 4th week
at the end of the pharynx and the beginning of the oesophagus, at the ventral wall of the foregut - respiratory diverticulum (lung buds) appear
43
how is the foregut divided in the 4th week
the trancheoesophageal septum develops and separates the respiratory diverticulum from the dorsal part of the foregut - in this way the foregut is divided into the ventral respiratory primordium & the dorsal oesophagus
44
what is the foregut divided into in the 4th week
1. the ventral respiratory primordium 2. the dorsal oesophagus
45
describe length of oesophagus
initially it is short but it lengthens rapidly with the descent of the heart and lungs
46
what are mesenteries
double layers or peritoneum that surround an organ and connect it to the body wall, such an organ is called intraperitoneal parts of the gut tube are suspended from the dorsal & ventral body walls by mesenteries
47
what is a retroperitoneal organ
when an organ is sitting directly on the posterior abdominal wall and covered by peritoneum on its anterior surface only
48
what are ligaments
double layers of peritoneum which pass from one organ to another or from one organ to the body wall
49
what do mesenteries and ligaments provide
pathways for blood vessels, lymphatics & nerves to go to and come from the abdominal viscera
50
what are the 2 mesenteries of the foregut
dorsal mesentary ventral mesentary
51
where does dorsal mesentery extend from
extends from the lower part of the oesophagus to the cloacal region (rectum)
52
what does dorsal mesentery do in 5th week
by the 5th week the lower part of the foregut, midgut & major part of the hindgut are suspended from the posterior abdominal wall by dorsal mesentery
53
where is the ventral mesentery
only in the region of the foregut - terminal part of the oesophagus, the stomach and the upper part of the duodenum
54
which mesenteries does the foregut have
both ventral and dorsal
55
which mesenteries do the midgut and hindgut have
only a dorsal mesentary
56
what is the ventral mesentery derived from
the septum transversum
57
what does the free lower margin of the ventral mesentery contain (3)
the hepatic artery portal vein bile duct
58
where does the liver develop
in the ventral mesentery
59
what does the liver divide the ventral mesentery into
into the lesser omentum & the falciform ligament
60
when does the foregut begin to dilate into the stomach
week 4 the stomach appears as a fusiform (spiral-shaped) dilation in the foregut in the 4th week
61
why does the appearance and position of the stomach change
it changes greatly as a result of the different rate of growth in various regions of its wall
62
how is the developing stomach attached to the body walls
by the dorsal & ventral mesenteries
63
which are nerves are on the sides of the stomach
left side of developing stomach = left vagus nerve right side of developing stomach = right vagus nerve
64
effect of the dorsal wall of the stomach growing faster than the ventral wall
this differential growth forms the greater & lesser curvatures of the stomach
65
what does the stomach do in the 7th week
the stomach rotates 90 degrees CLOCKWISE about a longitudinal axis - this rotate produces a space behind the stomach called the lesser sac
66
what happens to the greater and lesser curvature in the 7th week
the greater curvature (on the embryonic dorsal side) now faces the left of the body the lesser curvature (on the embryonic ventral side) faces the right
67
what happens to the left and right vagus nerve in the 7th week
the left vagus is now on the anterior side of the stomach the right vagus is located on the posterior side thus they are now called the anterior & posterior vagal trunks
68
what does the stomach do in the 8th week
the stomach and duodenum ROTATE about a ventrodorsal axis, pulling the end of the stomach upwards, they pull the duodenum into a C-shape results in the thinning of the dorsal mesentery, which now hangs from the greater curvature of the stomach - it is now called the greater omentum the ventral mesentery is now attached to the developing liver and has formed the lesser omentum
69
effect of the development of the omen and the rotations of foregut structures
produces distinct spaces of the peritoneal cavity
70
what is the lesser sac
the space posterior to the stomach
71
what is the greater sac
the space anterior to the stomach
72
how do the greater and lesser sacs communicate
via a small opening (located near the hilum of the liver) called the epiploic foramen
73
what do the anterior and posterior folds of the greater omentum do during the fetal period
they FUSE to form one THICK sheet formed from 4 layers of peritoneum
74
where does the liver grow from
liver bud is an outgrowth from the distal foregut (endotherm epithelium)
75
when does liver begin to develop
week 3
76
how does the liver deveelop
1. cells proliferate - grow into the septum transversum 2. connection between the liver bud and foregut (duodenum) narrows > bile duct 3. small outgrowth from the bile duct > gallbladder 4. as the liver grows the remaining mesoderm either side becomes membraneous > falciform ligament and lesser omentum
77
how does the pancreas develop
1. dorsal and ventral buds arise from the duodenum 2. dorsal bud develops in the dorsal mesentary 3. rotation of the stomach swings the ventral bud posteriorly 4. dorsal and ventral buds fuse
78
derivatves of the foregut
liver pancreas
79
what determines how regions of the gut tube develop
differential expression of transcription factors and genes along the tube
80
when does the gut tube start to differentiate
whilst lateral folding is bringing the ventral body wall together

GI lectures (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions