Flashcards in Development of Body Cavities Deck (43)
Intraembryonic coelem fate and names of what it forms
Major body cavities
Pericardial, pleural, and peritoneal
Development of coelem begins at
Definitive body cavities are present by week
Intraembryonic coelem communicates with
Chorionic cavity (extraembyronic coelem)
Communication between intraembryonic coelom and chorionic cavity allows
Herniation of gut into the extraembyronic space
Where and how is intraembyronic coelem isolated from chorionic cavity
Rostral and caudal ends
Lateral and longitudinal foliding
Intraembryonic coelom balloons and its walls form the
Visceral (splanchnic layer of mesoderm)
Parietal (somatic later of mesoderm)
Transverse folding does what to primitive right and left peritoneal cavities?
Brings them ventral
Later in time, during transverse folding, whathappens to right and left periotoneal cavities?
Fuse to form a continuous peritoneal cavity
Membranes that separate the two intraembryonic coeloms
Associated with the gut tube
What covers the developing gut tube?
Splanchnic mesoderm divides into
Dorsal and ventral mesentary
Continuous with one another
What are mesentaries ventral and dorsal to
Developing gut tube
When lateral folding is complete, what has occured?
Ventral mesentary has disappeared and intraembryonic coelom is seprated from extraembryonic
Why is dorsal mesentary maintained through life
Suspend the gut
Provide route for blood vessels, nerves, and lymphatics to reach gut
When does peritoneal cavity become continuous spece?
Loss of ventral mesentary
Leftover ventral mesentary that joins liver and stomach to upper duodenum
Leftover ventral mesentary that joints liver to anterior abdominal wall
Longitudinal folding repositions
Pericardial and heart tube to a more rostral position
Also moves the septum transversum
Mesodermal mass that is moved from between cardiogenic area and cranial margin of embryonic disk to between the cardiogenic area and the yolk sac
Spetum transversum divides
Intraembryonic coelom into pericardial/pleural cavity and peritoneal cavity
Large opening on each side of the future esophagus from the incomplete septum transversum
Esophagus formed from
Part of gut tube dervied from the definitive yolk sac that was incorporated into the embryo during folding
Lungs formed from
Ventral side of the gut tube
Seprate the pericardial cavity from the pleural cavities (lungs)
Close in the opening posterior to the septum transversum to separate adominopelvic cavity from the more rostral pleural cavities
First partition to develop in the intraembryonic coelom forms
Definitive adult pericardial and pleural cavities
Respiratory system comes from
Developing gut tube
Invade lateral body wall (lined by somatic meso) and carve out flaps of somatic mesoderm to begin to form pleuropericardial folds
Fibrous pericardium - function, origin, and what is it made out of?
Formed by merging of the pleuropericardial folds
Surrounds the heart
Made of somatic mesoderm
Thick mass of mesoderm between primitive heart and liver
Primordiu of central tendon of thoracic diaphragm
Pericardioperitoneal canals of intraembryonic coelom form the
Posterior opening between pericardial/pleural cavity and the peritoneal cavity
Paired pleuroperitoneal folds come from and where do they grow towards?
Come from Somatic mesoderm of the dorsolateral body wall
Grow towards the posterior border of the septum transversum
Pleuroperitoneal folds merge with ____ and why?
Posterior of septum transversum to close off the pericardioperitoneal cananls
Dorsal mesentary of the esophagus origin and what it forms
Mesentary invaded by myoblasts
Forms crura of the diaphragm
Body wall contributions
Myoblasts to peripheral bortion of the definitive diaphgram
Where do myoblasts from body wall originate?
C3,4,5 and form muscular part of the diaphragm
What folds does phrenic nerve pass through?
What happens as diaphragm descends?
Pulls phrenic nerve down to L1 due to rapid growth of the developing CNS
COngenital diaphragmatic hernia
Herniation of the abdominal contents into the pleural cavity caused by failure of pleuroperitoneal folds to develop or fuse with other components of the diaphragm
Abdominal contents press of the lungs
Clinical signs of congenital diaphragmatic hernia
Flat abdomen, breathlessness, and cyanosis
Left sided structures are shifted to the right