Embryology

Question 1

What gene is a transcription factor for establishing left sidedness?

Answer 1

PTX2

Question 2

Define gastrulation

Answer 2

formation of germ layers

Question 3

What structures develop from embryonic ectoderm?

Answer 3

Skin
CNS
PNS
Ear
Nose
Throat

Question 4

What structures develop from embryonic endoderm?

Answer 4

Epithelial lining of respiratory system
GIT
Glands
Liver
Pancreas
Urinary bladder

Question 5

What structures develop from embryonic mesoderm?

Answer 5

Muscles
Bones
Cartilage
Urogenital system

Question 6

What week is the gut tube formed?

Answer 6

During 3rd and 4th

Question 7

What gives rise to parietal and visceral mesoderm?

Answer 7

Lateral plate mesoderm

Question 8

What is the gut tube closed by at its cranial end?

Answer 8

Oropharyngeal membrane

Question 9

What is the gut tube closed by at its caudal end?

Answer 9

Cloacal membrane

Question 10

What secretes sonic hedge hog cells?

Answer 10

Gut endodermal cells

Question 11

What is the function of SHH?

Answer 11

Organisation of gut

Question 12

Where does ventral mesentary form from?

Answer 12

Caudal end

Question 13

What mesentery hangs gut tube from body wall?

Answer 13

Dorsal

Question 14

Where does the oesophagus develop from?

Answer 14

The cranial part of the gut tube

Question 15

What is the function of the Tracheo-oesophageal septum

Answer 15

Divides oesophagus from trachea

Question 16

What does the lung bud develop from?

Answer 16

Outgrowth of the ventral wall of the foregut

Question 17

What forms the stomach?

Answer 17

Foregut caudal of oesophagus dilates to form the stomach

Question 18

What part of the stomach does the left vagus supply?

Answer 18

Anterior wall of stomach

Question 19

What part of the stomach does the right vagus supply?

Answer 19

Posterior part of stomach

Question 20

What is the stomach attached to the dorsal and ventral wall by?

Answer 20

A mesentery called mesogastrium

Question 21

What forms the lesser sac?

Answer 21

Rotation along the longitudinal axis pulling the dorsal mesentery to the left

Question 22

What is the duodenum formed from?

Answer 22

Caudal part of the foregut
Cranial part of the midgut

Question 23

What artery supplies the duodenum below the opening of the bile gut?

Answer 23

Superior mesenteric artery

Question 24

What artery supplies the duodenum above the opening of the bile duct?

Answer 24

Coeliac trunk

Question 25

Is the duodenum retroperitoneal or intraperiotoneal?

Answer 25

Retroperitoneal except the duodenal cap

Question 26

What gives rise to the gallbladder?

Answer 26

Liver bud

Question 27

When is the liver bud formed?

Answer 27

Week 3

Question 28

What liver parts are endodermal origin?

Answer 28

Hepatocytes Biliary epithelial

Question 29

What liver and biliary apparatus are mesodermal origin?

Answer 29

Kupffer cells Haemotopoietic cells Connective tissue

Question 30

What does the falciform ligament and momentum develop from?

Answer 30

Ventral mesentary

Question 31

When is bile formed?

Answer 31

12th week

Question 32

What is the origin of the spleen?

Answer 32

mesoderm

Question 33

What connects the spleen and kidney?

Answer 33

splenorenal ligament

Question 34

What happens to the spleen in weeks 15 to 17 of gestation?

Answer 34

Colonised by T-lymphocytes

Question 35

What happens to the sleep in week 23 gestation?

Answer 35

The b-cell precursors arrive and spleen starts it's lymphoid function

Question 36

What forms the head of the pancreas?

Answer 36

Duodenum rotates so the ventral bud also moves closer to the dorsal bud

Question 37

When does the pancreas and spleen form?

Answer 37

Week 5

Question 38

When does the head of the pancreas form?

Answer 38

Week 6

Question 39

What is the result of incomplete separation of the lung bud?

Answer 39

Oesophageal atresia Tracheo-oesophageal fistula

Question 40

Give examples of developmental anomalies in the foregut

Answer 40

Double gallbladder Stricture of duodenum Annular pancreas

Question 41

Where does the midgut extend from?

Answer 41

From opening of bile duct into the duodenum to proximal 2/3rds of the transverse colon

Question 42

What way does the primary intestinal loop rotate?

Answer 42

Anti-clockwise

Question 43

What happens to the primary intestinal loop in week 6?

Answer 43

Physiological herniation of intestinal loop

Question 44

What does the Vitelline duct connect?

Answer 44

Ileium with yolk sac

Question 45

When do the intestinal loops move back into abdominal cavity?

Answer 45

Week 10

Question 46

What week does the cecal bud develop?

Answer 46

Week 6

Question 47

What does the cecal bud form from?

Answer 47

Caudal part of loop S. intestine forms

Question 48

What happens to the midgut loop?

Answer 48

Elongates needs will differentiate into different parts of intestines

Question 49

What are some common developmental abnormalities of the midgut?

Answer 49

Stenosis Malrotation

Question 50

What is omphalocele?

Answer 50

Failure of retraction of herniated intestinal loop though umbilical ring at week 10

Question 51

What may vitelline duct form if it persists?

Answer 51

Fistula Cyst Ligament Meckel's diverticulitis

Question 52

What parts of the hindgut are ectodermal origin?

Answer 52

Lower part of anal canal and anal orifice

Question 53

When does the cloacal membrane rupture?

Answer 53

week 7

Question 54

What part of the anal canal is endodemral origin?

Answer 54

Cranial part

Question 55

What part of the anal canal is ectodermal origin?

Answer 55

Caudal anal canal

Question 56

What are some common hindgut developmental anomalies?

Answer 56

Urorectal fistula Rectovaginal fistula Rectoperineal fistual Imperforated anus