Embriology

Question 1

Origin of epith of digestive tract + parenchyma of some glands

Answer 1

Endoderm

Question 2

Origin of muscle walls of viscera + CT layers surrounding viscera

Answer 2

Mesoderm

Question 3

Liver arises from

Answer 3

Liver bud

Question 4

Liver bud protrudes into

Answer 4

Ventral mesogastrium

Question 5

Ventral mesogastrium divides into

Answer 5

Gastrohepatic / lesser omentum
Falciform ligament

Question 6

Gastrohepatic / lesser omentum connects

Answer 6

Stomach and liver

Question 7

Falciform ligament connects

Answer 7

Liver to the ventral wall

Question 8

Liver location

Answer 8

R side

Question 9

Liver functions

Answer 9

Glycogen production
Albumin production
Protein metabolism
Bile secretion
Hematopoietic function (after embryonic splanchnic mesoderm)

Question 10

Bile is stored in

Answer 10

Gallbladder

Question 11

Gallbladder origin

Answer 11

Hepatic duct grows and gives it

Question 12

Gallbladder is connected to the liver by

Answer 12

Cystic duct

Question 13

Gallbladder reaches duodenum through

Answer 13

Common bile duct

Question 14

Pancreas origin from

Answer 14

Ventral + dorsal pancreatic duct
They fuse and for the head, neck and body

Question 15

Ventral pancreatic duct arises from

Answer 15

Common bile duct

Question 16

Relation main pancreatic duct - duodenum

Answer 16

It opens through the common bile duct into the 2nd portion of the duodenum, so both hepatic and pancreatic secretions enter here to participate in digestion.

Question 17

Accessory pancreatic duct origin

Answer 17

Dorsal pancreas duct that persist a persist as a little accessory pancreatic duct

Question 18

Accessory pancreatic duct function

Answer 18

When the main pancreatic duct is blocked

Question 19

Separation between the derivatives of the foregut and the derivatives from the midgut

Answer 19

Major duodenal papilla

Question 20

Major duodenal papilla marks

Answer 20

Point where main pancreatic duct and bile duct drain into duodenum

Question 21

Minor duodenal papilla

Answer 21

Where accessory pancreatic duct drains into the duodenum in case of blockage of the main one

Question 22

Stomach formation

Answer 22

It rotates around its long axis 90º clockwise —> behind it appears ommental bursa / lesser sac

Post walls grow faster —> increased curvature on L side

Cardiac portion: downwards
Pyloric portion: upwards

Question 23

Stomach is connected and attached by

Answer 23

Mesenteries

Question 24

Liver arises within

Answer 24

Ventral mesogastrium

Question 25

Pancreas and spleen arise within

Answer 25

Dorsal mesogastrium

Question 26

Dorsal mesogastrium gives rise to

Answer 26

Greater omentum

Question 27

Mesenteries definition

Answer 27

Double layer of peritoneum

Question 28

Mesenteries function

Answer 28

Connects viscera to dorsal and ventral walls

Question 29

Esophagus formation

Answer 29

From foregut ventral wall —> respiratory diverticulum that will be separated from esophagus by tracheoesophageal septum

Question 30

Anomalies in esophagus formation

Answer 30

Tracheoesophageal fistulas —> prenatal: polyhydramnios / postnatal: regurgitation) Incomplete recanalization (stenosis) Congenital hiatal hernia —> stomach herniates into thoracic cavity

Question 31

Midgut definition

Answer 31

Part of the gut tub that remains connected to the yolk sac after the folds progresses. Connected to abdominal wall by dorsal mesentery through which arteries can access

Question 32

Midgut location

Answer 32

Inferiorly to major duodenal papilla -> junction prox 2/3 - distal 1/3 of transverse colon

Question 33

Disposition changes of the midgut

Answer 33

(Dorsal mesentery rotates along w/ structures) 5th week: U-shape loop has sup+inf limb & vitelline duct 6th week: midgut limb growth + not enough space = physiological herniation into umbilicus (90º rotation) —> sup limb to R (small intest loops), inf limb to L (large intest derivatives) 10th week: enough space -> physiolog hernia reduction —> inf limb also enters but rotates 180º

Question 34

Anomalies of the midgut development

Answer 34

Malrotation Meckel’s diverticulum - by persistence of vitelline duct Umbilical hernia - by unproperly abd musculature closure Omphalocele - by failure of reduction of physiolog herniat. Gastroschisis - by incomplete closure of lat folds (viscera bathed by amniotic fluid)

Question 35

Hindgut location

Answer 35

Begins just before L colic flexure/ splenic flexure Ends in the cloacal membrane

Question 36

Caudal portion of the hindgut =

Answer 36

Cloaca

Question 37

Post to the cloaca is the

Answer 37

Allantois

Question 38

Allantois is related to

Answer 38

Bladder and urogenital system

Question 39

Hindgut is separated from allantois by

Answer 39

Urorectal septum

Question 40

Urorectal septum definition

Answer 40

Mesoderm ridge that will form the perineum

Question 41

Urorectal septum development

Answer 41

Will grow caudally and separate cloaca into - ant: allantois - post: rectum and anal canal Will separate the cloacal membrane into - urogenital membrane - anal membrane

Question 42

Cloacal membrane gives rise to

Answer 42

Proctodeum

Question 43

Anal canal origins

Answer 43

- 1º 2/3 of anal canal —> from hindgut - last 1/3 of anal canal -> from proctodeum (= ectoderm invagination)

Question 44

Last portion of anal canal innervation and irrigation

Answer 44

Innervation: somatic Irrigation: inf and middle rectal veins -> common iliac veins

Question 45

Anal membrane rupture

Answer 45

8th week

Question 46

Congenital anomalies of the hindgut

Answer 46

Incorrect development of urorectal septum - imperforate anus - rectovaginal fistula - fistula ureters-rectum - rectal atresia Megacolon/ Hirschsprung disease (non-proper migration of NCC during 4-5th week = no PS ganglia = no peristalsis = food accumulation = dilation)