Development of Body Cavities

Question 1

Intraembryonic coelem fate and names of what it forms

Answer 1

Major body cavities

Pericardial, pleural, and peritoneal

Question 2

Development of coelem begins at

Answer 2

Week 3

Question 3

Definitive body cavities are present by week

Answer 3

8

Question 4

Intraembryonic coelem communicates with

Answer 4

Chorionic cavity (extraembyronic coelem)

Question 5

Communication between intraembryonic coelom and chorionic cavity allows

Answer 5

Herniation of gut into the extraembyronic space

Question 6

Where and how is intraembyronic coelem isolated from chorionic cavity

Answer 6

Rostral and caudal ends

Lateral and longitudinal foliding

Question 7

Intraembryonic coelom balloons and its walls form the

Answer 7

Visceral (splanchnic layer of mesoderm)

Parietal (somatic later of mesoderm)

Question 8

Transverse folding does what to primitive right and left peritoneal cavities?

Answer 8

Brings them ventral

Question 9

Later in time, during transverse folding, whathappens to right and left periotoneal cavities?

Answer 9

Fuse to form a continuous peritoneal cavity

Question 10

Mesenteries

Answer 10

Membranes that separate the two intraembryonic coeloms

Associated with the gut tube

Question 11

What covers the developing gut tube?

Answer 11

Splanchnic mesoderm

Question 12

Splanchnic mesoderm divides into

Answer 12

Dorsal and ventral mesentary

Continuous with one another

Question 13

What are mesentaries ventral and dorsal to

Answer 13

Developing gut tube

Question 14

When lateral folding is complete, what has occured?

Answer 14

Ventral mesentary has disappeared and intraembryonic coelom is seprated from extraembryonic

Question 15

Why is dorsal mesentary maintained through life

Answer 15

Suspend the gut

Provide route for blood vessels, nerves, and lymphatics to reach gut

Question 16

When does peritoneal cavity become continuous spece?

Answer 16

Loss of ventral mesentary

Question 17

Lesser omentum

Answer 17

Leftover ventral mesentary that joins liver and stomach to upper duodenum

Question 18

Flaciform ligament

Answer 18

Leftover ventral mesentary that joints liver to anterior abdominal wall

Question 19

Longitudinal folding repositions

Answer 19

Pericardial and heart tube to a more rostral position

Also moves the septum transversum

Question 20

Septum Transversum

Answer 20

Mesodermal mass that is moved from between cardiogenic area and cranial margin of embryonic disk to between the cardiogenic area and the yolk sac

Question 21

Spetum transversum divides

Answer 21

Intraembryonic coelom into pericardial/pleural cavity and peritoneal cavity

Question 22

Pericardioperitoneal canals

Answer 22

Large opening on each side of the future esophagus from the incomplete septum transversum

Question 23

Esophagus formed from

Answer 23

Part of gut tube dervied from the definitive yolk sac that was incorporated into the embryo during folding

Question 24

Lungs formed from

Answer 24

Ventral side of the gut tube

Question 25

Pleuropericardial folds

Answer 25

Seprate the pericardial cavity from the pleural cavities (lungs)

Question 26

Pleuroperitoneal folds

Answer 26

Close in the opening posterior to the septum transversum to separate adominopelvic cavity from the more rostral pleural cavities

Question 27

First partition to develop in the intraembryonic coelom forms

Answer 27

Definitive adult pericardial and pleural cavities

Question 28

Respiratory system comes from

Answer 28

Developing gut tube

Question 29

Lung growth

Answer 29

Invade lateral body wall (lined by somatic meso) and carve out flaps of somatic mesoderm to begin to form pleuropericardial folds

Question 30

Fibrous pericardium - function, origin, and what is it made out of?

Answer 30

Formed by merging of the pleuropericardial folds Surrounds the heart Made of somatic mesoderm

Question 31

Septum transversum

Answer 31

Thick mass of mesoderm between primitive heart and liver | Primordiu of central tendon of thoracic diaphragm

Question 32

Pericardioperitoneal canals of intraembryonic coelom form the

Answer 32

Posterior opening between pericardial/pleural cavity and the peritoneal cavity

Question 33

Paired pleuroperitoneal folds come from and where do they grow towards?

Answer 33

Come from Somatic mesoderm of the dorsolateral body wall | Grow towards the posterior border of the septum transversum

Question 34

Pleuroperitoneal folds merge with ____ and why?

Answer 34

Posterior of septum transversum to close off the pericardioperitoneal cananls

Question 35

Dorsal mesentary of the esophagus origin and what it forms

Answer 35

Mesentary invaded by myoblasts | Forms crura of the diaphragm

Question 36

Body wall contributions

Answer 36

Myoblasts to peripheral bortion of the definitive diaphgram

Question 37

Where do myoblasts from body wall originate?

Answer 37

C3,4,5 and form muscular part of the diaphragm

Question 38

What folds does phrenic nerve pass through?

Answer 38

Pleuropericardial folds

Question 39

What happens as diaphragm descends?

Answer 39

Pulls phrenic nerve down to L1 due to rapid growth of the developing CNS

Question 40

COngenital diaphragmatic hernia

Answer 40

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

Question 41

Lung hypoplasia

Answer 41

Abdominal contents press of the lungs

Question 42

Clinical signs of congenital diaphragmatic hernia

Answer 42

Flat abdomen, breathlessness, and cyanosis | Left sided structures are shifted to the right

Question 43

4 things contributing to the thoracic diaphragm

Answer 43

Septum transversum Paired pleuroperitoneal folds Dorsal mesentary of the esophagus Body wall