The document discusses the embryology of the digestive system. It begins by explaining the embryonic origins of tissues from the endoderm, splanchnic mesoderm, and neural crest. It then describes the foregut, midgut, and hindgut, and their derivatives. Key points include the embryonic folding causing rotation of the stomach and intestines. The development of various organs is covered, such as the esophagus, liver, pancreas, and intestines. The intestines initially herniate through the umbilicus before retracting. Congenital anomalies that can occur in each part are also outlined.

1. EMBRYOLOGY OF THE DIGESTIVE
SYSTEM
PRESENTATION BY
GROUP 7
Members ;

2. EMBRYONIC FOLDING AND ITS EFFECTS
2

3. 3

4. EMBRYONIC ORIGIN OF VARIOUS TISSUES AND
ORGANS
ENDODERM SPLANCHIC MESODERM NEURAL CREST
1.epithelial lining of gut wall
2.exocrine glands both
intrinsic and extrisinc types
1.connective tissue element
of mid gut
2.smooth mascular of gut
wall
3. mesentry
1.migratory and ivade
developing gut tube
2.give rise to enteric
nervous plexus of the gut
wall ie mysentric nerve
plexus and submucosal
nerve plexus
4

5. PARTS AND DERIVATIVES OF EACH PART OF THE
PRIMORDIAL GUT
5
FOREGUT MID GUT HIND GUT
1.Gut -pharynx to the 1.Small gut 1.distal parts of the large
duodenum(D2) (duodenum,jejunum,ileum) gut(transverse
2.Extrinsic 2.large colon ,descendig
glands(liver,pancreas,billary gut(caecum,appendix,ascen colon,sigmoid colon)
tree)
3.Lower respiratory tract
ding colon,2/3of the
transverse colon)
.cloaca :anal canal

6. Derivatives of the primiordial gut
6

7. Development of the esophagus
The respiratory
diverticulum forms forms
from the ventral aspect of
the fore gut
The foregut undergoes
septation process to
separate the esophagus
and the trachea
Elongation takes place
Esophagus enters the
solidstage of
development
Recanalization takes place
7

8. Congenital anormalies of the esophagus
8

9. Development of the stomach
9

10. Vertical rotation

About 90 degrees
clockwise
The greater curvature
goes to the left and the
lesser curvarture goes to
the right

10

11. Rotation in the anteroposterior direction
 About 60 to 70
degrees clockwise
The fundus goes
downwards and to the left
side
The pylorus goes upwards
and to the right side


11

12. Congenital anomalies of the stomach
12

13. Development of the duodenum
 During the fourth week
of gestation the
duodenum
begins to develop from
two sources;the cranial
part of
midgut and caudal part
of foregut.
The developing
deudonum forms a c

13

14. Development of the hepatobillary sytem (liver,bile
ducts and gall bladder)
14

15. continuation
15

16. Development of the pancreas
16

17. Congenital anomarlies of hepatobillary system
17

18. Congenital anomarlies of the pancreas
18

19. Development of the intestines

19
The intestines arise from
mainly the midgut and hind
gut
Rapid proliferation by the
endodermal cells causes rapid
elongation of the midgut that
forms the primary intestinal
loop which divides to form the
cephalic limb and the caudal
limb.
Apex of loop is stilla attached



20. Physiological
umbilical
herniation.
 During the 6th week of
gestation, the intestinal
loop
herniates through the
umbilicus ,for further
development in the
greater space outside.
20

21. Continuation.
 During physiological
umbilical herniation ,also
external
rotation occurs of 90
degrees anticlockwise
about the
superior mesentric artery.
Results into the cephalic
limb on the right and caudal
limb to the left.

21

22. contiunuation
Why development occurs
outside the abdomen of
feotus?
 Due to the rapid growth
and expansion of the liver
.
22

23. Reduction herniation/retraction of herniated loops.

It occurs around the 10th week
of
gestation ,with the duodenum
coming first followed by the
small
intestines ,large intestines.
During return,large gut rotates
180 degrees anticlockwise
about superior mesentric
artery.
Results into the large gut


23

24. continuation
24

25. 25

26. 26

27. Development of the intestines
summar
y
27

Site of origin:distal foregut,whole mid gut and hind gut
Rapid proliferation ,leading to elongation and formation of the
primary intestinal loop.
Physiological umbilical herniation with external rotation of
90degrees anticlockwise
Continued development within the hernial sac ,involution of the
vitellineduct.
Hernia reduction (beginning from the duodenum,small
intestines,large intestines) with internal rotation of 180 degrees
anticlockwis






28. Congenital anomalies of intestines
28

29. 29

30. 30

31. 31

32. Cloacal partitioning
 The cloacal is the common
union of the hindgut
(digestive system )
and allontios (urinary system)
Undergoes partioning by
the urorectal septum in to
two chambers .
The anterior chamber is called
the urogenital sinus ,while the
posterior chamber is the ano
rectal canal.


32

33. 33

34. Congenital anomalies
34

35. 35

36. 36

37. 
37
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attention