GI embryology And Histology

Question 1

what does the foregut enclose and what is it supplied by and innnervation

Answer 1

Oesophagus liver, stomach, part of duodenum and spleen, supplied by coeliac trunk
Greater splanchnic

Question 2

midgut encompasses and vasculature and innervation

Answer 2

1/2 of dueodenum , jejunum and ileum to 2/3 of transverse colon , by Sma lesser splanchnic

Question 3

hindgut and vasculature and innervation

Answer 3

1/3 of transerve colon to anal canal
Supplied by ima
Least splanchnic

Question 4

where is visceral pain felt in the foregut

Answer 4

epigastric region

Question 5

mesentries of theforegut

Answer 5

dorsal and ventral

Question 6

What happens in elongation

Answer 6

the vitaline duct grows and growth of mesentary

loops - primary intestinal loop

Question 7

where is the caudal limb

Answer 7

distal part of ileum

Question 8

Histology of lips and tongue

Answer 8

Outer lips highly keratinised
Inner less
Ventral tongue non keratanising squamous epithelium
Dorsal tongue is keratinised

Question 9

Histology of Oesophagus

Answer 9

Stratified squamous non keratanising

Question 10

Histology of stomach

Answer 10

Simple Columnar

Question 11

Histology of Small and large intestine, rectum and Anus

Answer 11

Small simple columnar with crypts and villi
Colon is simple columnar and rectum
Anal canal stratified squamous

Question 12

Duodenum histology

Answer 12

Few pilcae circulares
Few goblet cells
Long crypts

Question 13

Histology of jejunum

Answer 13

Close packed pilcae circulares
Many goblet cells
Short crypts

Question 14

Colon histology

Answer 14

All looks the same
No villi
Muscularis externa , into three longitudinal bands

Question 15

How would stomach cells stain

Answer 15

Parietal cells are cuboidal with a dark standing nucleus

Chief cells would stain purple with blue nucleus

Question 16

What are tastebuds

Answer 16

Peripheral chemoreceptors in the epithelium of upper / dorsal surface of the tongue , soft palate as well as pharynx

Question 17

Function of a tastebud

Answer 17

Transduction of a chemical stimuli into a nervous signal

Question 18

How many types of taste buds

Answer 18

4

Question 19

Nerves involved in innervating the taste buds

Answer 19

Facial
Glossopharangyeal
Vagus

Question 20

Facial nerve and taste buds

Answer 20

Innervates anterior 2/3 on tongue

Question 21

Glossopharangyeal and taste buds

Answer 21

Posterior 1/3 on tongue

Question 22

Vagus nerve and tastebuds

Answer 22

Epiglottis region and pharanygeal

Question 23

From what germ layer does the gt system form

Answer 23

Endoderm

Question 24

Midgut development

Answer 24

Rapid elongation makes the 1 intestinal loop
Rotates and herniates due to lack of space in abdom cavity

It then retracts as there is more space ( 3 months. )

Question 25

Development of stomach and Oesophagus and innervation

Answer 25

Cn10 Endoderm Expansion of primitive gut tube makes the Oesophagus Stomach rotates 90* Growth of posterior stomach gives rise to greater curvature

Question 26

What does the dorsal mesentery of the stomach become

Answer 26

Greater omentum

Question 27

Embryology of pancreas

Answer 27

``` Originated as two buds Dorsal - neck body , tail part of head Ventral - uncinate process part of head Buds undergo rotation , Exocrine and endocrine cells are a foregut derivative ```

Question 28

Histology of exocrine pancreas

Answer 28

Serous acinar , simple epithelium Lobulated connective tissues that stains dark Beta cells stain blue by aldehyde fuchsin

Question 29

Ducts of pancreas epithelia

Answer 29

Simple columnar epithelia

Question 30

Histology of sinusoids

Answer 30

Lined with endothelial cells and flanked by plates of hepatocytes

Question 31

Portal triad histology

Answer 31

Wrapped in connective tissue | Bile duct is cuboidal epithelium

Question 32

Histology in endocrine pancreas

Answer 32

Pancreatic islet of langerhans