Development Of Gut (1) Flashcards
What process forms the trilaminar disc?
Gastrulation
What are the 3 layers of the trilaminar disc?
Ectoderm
Mesoderm
Ectoderm
What are the 3 sections of the mesoderm?
Paraxial mesoderm
Intermediate mesoderm
Lateral plate mesoderm
What does the paraxial mesoderm give rise to?
Somites
What do somites form?
Vertebrae
Skeletal muscles
Cartilage
Tendons
What does the intermediate mesoderm give rise to?
Kidneys
Gonads
What 2 types of mesoderm does the lateral plate mesoderm form?
Somatic mesoderm
Splanchnic mesoderm
What 2 types of mesoderm does the lateral plate mesoderm form?
Somatic mesoderm
Splanchnic mesoderm
What does the splanchnic mesoderm form?
Viscera
What does the somatic mesoderm form?
Associated with body walls
What does the ectodermal give rise to?
Epidermis of skin
Hair
Nails
CNS
PNS
What does the endoderm give rise to?
Forms epithelial lining of GI tract
What 2 planes does the trilaminar disc fold in?
Sagittal folding
Lateral folding
Describe the Sagittal folding of the trilaminar disc:
Cranio-caudal folding occurs creating a head and tail end of the embryo
What forms the amniotic cavity? (look at slide 5)
Somatic lateral plate of mesoderm surrounds the ectoderm
What forms the yolk sac? (look at slide 5)
Endoderm surrounded by the splanchnic lateral plate mesoderm
What are the 3 parts that the endoderm differentiates into?
Foregut
Midgut
Hindgut
What does the foregut form?
Oesophagus to the 2nd part of the duodenum where the bileduct and pancreas join
Where does the midgut span to?
From the 2nd part of the duodenum to the distal 2/3rds of the transverse colon
Where does the hindgut span to?
Distal 2/3 transverse colon to upper anal canal
What is a blind ended diverticula? where are they found?
No opening where the mouth and anus form
What is the connection between the midgut and the yolk sac called?
Vitelline duct
What can happen if the vitellin duct doesn’t obliterate at birth?
What is the condition called?
There’s a connection between midgut and umbilicus meaning faecal maternal can come out the umbilicus
Meckels diverticulum
What is the intraembryonic coelom?
The space between the splanchnic mesoderm and the somatic mesoderm
What does the intraembryonic coelom give rise to?
Thoracic cavities
Abdominal cavities
What is the splanchnopleuric mesoderm?
What does it form?
It’s derived from lateral plate mesoderm
Splanchnic mesoderm + endoderm
Forms viscera
What is somatopleuric mesoderm?
What does it form?
Derived from lateral plate mesoderm
Somatic mesoderm + ectoderm
Body walls + dermis
What is peritoneum (serous membrane lining abdominal cavity) derived from?
Lateral plate mesoderm
What part of the lateral plate mesoderm forms the parietal peritoneum?
Somatic portion of lateral plate mesoderm
What part of the lateral plate mesoderm forms the visceral peritoneum?
Splanchnic portion or lateral plate
