Development of midgut and hindgut

Question 1

At ——- week the midgut consist of simple loop suspended and supplied by —————– in the —————-mesentery

Answer 1

5th - superior mesenteric - dorsal

Question 2

Midgut communicate with yolk sac through ————-

Answer 2

Vitelline duct

Question 3

midgut simple loop swelling in the caudal limb marks the future ——————–

Answer 3

caecum

Question 4

midgut derivative : The cranial limb elongates greatly
to form the ———– and two-thirds
of the ————

Answer 4

jejunum-ileum

Question 5

The proximal part of the
vitelline duct persists in 2%
of individuals as —————————

Answer 5

Meckel’s

diverticulum

Question 6

the caudal limb of midgut will form ————-,————,—————-,—————,————-

Answer 6

Distal end of ileum- Cecum - appendix - ascending colon- Rt 2/3 of Transverse colon

Question 7

Midgut Herniation =
At ———- week the midgut loop
elongates rapidly and the———
enlarges. The abdominal cavity
becomes relatively ——— and part of
the intestine herniates into the
——————, through the coelomic opening next to the umbilical cord.

Answer 7

6
liver
small
extra-embryonic coelom

Question 8

Midgut Retraction
During the ————- week the abdomen enlarges
and the intestine returns into the abdominal
cavity. As this occurs, the midgut loop ———-
so that the different parts of the intestine
acquire their definitive positions in the
abdominal cavity

Answer 8

10th

rotates

Question 9

How many positions of Caecum during development ?

Answer 9

3

Question 10

Midgut Rotation
- The caecum in the caudal limb
of the midgut, the loop is taken 
landmark for rotation. 
- It rotates through a total 
of---------------- to acquire its definitive position. 
The rotation occurs in ------- stages: 
a. At ----- week: -------- anticlockwise - 
the caecum is shifted to the -----------
b. At -------- week: --------------- - the
caecum acquires its definitive position
Three positions of the caecum
during midgut development

Answer 10

270° anticlockwise-two-6th-90°-left-10th-180° anticlockwise

Question 11

Caecum situated caudally
————week
Caecum below a
the ————-lobe of liver Caecum in right
———–week
Caecum in the right iliac fossa—– week

Answer 11

6th -right -10th-11

Question 12

Congenital anomalies
——————-Clockwise rotation results in intestinal situs inversus
- Failure of rotation may result in left-sided caecum
appendix and ascending colon
- Incomplete rotation - subhepatic caecum and appendix )

Answer 12

Malrotation of the gut

Question 13

Congenital anomalies
————– is a rotation of an intestinal loop around is
a branch of the superior mesenteric artery - it may
cause intestinal obstruction or even gangrene

Answer 13

Volvulus

Question 14

Congenital anomalies
——————— is the invagination of a segment of intestine it self
causing obstruction

Answer 14

Intussusception

Question 15

4. Persistent Vitello-intestinal Duct and
   Meckel’s Diverticulum
   There are various degrees of persistence of vitelline
   duct:
   - ————— - meconium oozes out of umbilicus
   - ————— - part of duct is not obliterated
   - ————— - attaches ileum to umbilicus
   - ————— - persistent proximal part of
   vitelline duct occurs in 2% of normal individuals

Answer 15

Vitelline fistula
Vitelline cyst
Vitelline cord
Meckel’s diverticulum

Question 16

Gastroschisis
- Herniation of viscera through
---------------------------------
into the amniotic cavity
- to the-----------------of the umbilicus
* no covering membranes; viscera
bathed directly in amniotic fluid.
- ------------ commonly associated with
other anomalies

Answer 16

ruptured abdominal wall defect
right
less

Question 17

Omphalocele
- Herniation of abdominal viscera
through a ---------------------
- defect of ---------------- mesoderm
- Viscera covered by ----------and
---------------------
- 50% have other serious congenital or chromosome
abnormalities

Answer 17

large umbilical ring
lateral plate
peritoneal +amniotic membrane

Question 18

The Hindgut
--------- days: After formation of the tail
fold, the allantois and hind gut open
 (into a common chamber the cloaca.
The cloacal membrane separates
--------- from the ----------
The allantois
appears at about---------- days 
small diverticulum projecting _
from the caudal end of the yolk
sac into the connecting stalk .
The ----------------septum separates the
hindgut from the allantois. It grows
towards the cloacal membrane. It is
derived from --------------at the
junction between the connecting stalk
and yolk sac.

Answer 18

26-cloaca-proctodeum.
16
urorectal
mesoderm

Question 19

The urorectal septum separates the
------- from the ----------. It grows
towards the cloacal membrane. It is
derived from ----------at the
junction between the connecting stalk
and yolk sac.

Answer 19

hindgut-allantois

mesoderm

Question 20

The urorectal septum grows towards
the -------------- but does not
fuse with it. It is derived from
---------- at the junction between the
connecting stalk and yolk sac.

Answer 20

cloacal membrane-mesoderm

Question 21

During the ———-week the cloacal
membrane disappears, exposing a
ventral ————– opening
and a ———–.

Answer 21

7th -urogenital sinus-dorsal anal opening

Question 22

The tip of the urorectal septum, Separating

the two openings forms the ———-body.

Answer 22

perineal

Question 23

The Anal Canal
-At the end of the ---------- week,
after rupture of the cloacal
membrane, proliferation of
------ occludes the anal opening

Answer 23

8th-ectoderm

Question 24

During the———— week the opening is

recanalized

Answer 24

9th

Question 25

Thus the terminal part of the anal
canal is ———— in origin and is
supplied by the ———–

Answer 25

ectodermal-inferior rectal artery

Question 26

The junction between ectoderm and

endoderm is the ————-.

Answer 26

pectinate line

Question 27

Congenital anomalies of large intestine
Aganglionic Megacolon - Hirschsprung Disease
Due to congenital absence of ————–
ganglia in the colon. This is a ——— migration defect.
It varies in extent -
80% involve —– and ———
3% involve the whole colon.

Answer 27

parasympathetic
neural crest
sigmoid colon
rectum:

Question 28

Imperforate anus

baby has an improperly developed anus, and therefore can t pass ———- normally from his rectum out of the body.

Answer 28

Stool

ينزل بول و بطنه تكون منتفخة

Question 29

lower part of anal canal arise from —————(———-)

Answer 29

Proctodeum ( Ectoderm)

Question 30

During week ———-anal membrane ruptures and anal canal open in tail region (osmosis)

Answer 30

7th