Non-cardiac embryology

Question 1

Where is the intraembryonic coelom located? What are its three cavities

Answer 1

1. Located between the parietal and viseral layers of lateral plate mesoderm
2. Pericardial cavity at cranial end, Pleural cavity at arm, and Peritoneal cavity at caudal end

Question 2

What does lateral folding do?

Answer 2

Brings lateral extensions (arms) of intraembryonic coelom together ventrally

Forms pleural cavity and peritoneal cavity

Question 3

What does longitudinal folding do?

Answer 3

1. Pericardial cavity forms: moves ventrally and caudally
2. Septum transversum forms: moves caudal to pericardial cavity

Question 4

After folding what is anterior and posterior to the foregut?

Answer 4

anterior: pericardial cavity
posterior: septum transversum and peritoneal cavity

Question 5

Which membrane separates the pericardial cavity from the peritoneal cavity?

Answer 5

Septum transversum

Question 6

What is the pericardioperitoneal canal?

Answer 6

Small tube connecting pericardial cavity and peritoneal cavity

Question 7

What membrane separates the lungs and heart?

Answer 7

pleuropericardial membrane

Question 8

What separates the two lungs?

Answer 8

Esophagus mesentery

Question 9

What is congenital disphragmatic hernia (CDH)?

Answer 9

Failure of the pericardioperitoneal canals to close (intestines move out of diaphragm)

Question 10

Pleuropericardial membrane

1. Derived from what layer
2. What does it contain?

Answer 10

1. Parietal layer of lateral plate mesoderm
2. contain common veins and phrenic nerves

Question 11

Pleuroperitoneal membrane

1. What does it fuse with?

Answer 11

1. Septum transversum and dorsal mesentery of the esophagus

Question 12

What does the gut tube form from?

Answer 12

Endoderm

Question 13

What forms the trachea?

Answer 13

Respiratory diverticulum (bud out from foregut)

Question 14

What separates the respiratory diverticulum from the foregut?

Answer 14

Tracheoesophageal ridge

Question 15

What is tracheoesophageal fistula?

Answer 15

Incomplete ridge -> trachea and esophagus are connected

Question 16

What forms the fibrous pericardium and phrenic nerves?

Answer 16

Pleuropericardial membranes (from parietal layer)

Question 17

What does the pericardioperitoneal canals become?

Answer 17

Pleural cavities

Question 18

What does the septum transversum become?

Answer 18

central tendon of diaphragm

Question 19

What does the dorsal mesentery of the esophagus become?

Answer 19

Crura (underside) of the diaphragm

Question 20

What does the body wall become?

Answer 20

Muscles at lateral edges of diaphragm

Question 21

What do the cervical somites (C3-5) become?

Answer 21

diaphragm muscles

Question 22

What does the respiratory diverticulum become?

Answer 22

Trachea and bronchi

Question 23

Name all the things that the visceral layer of lateral plate mesoderm becomes

Answer 23

1, Lung smooth muscle

2. Alveolar capillaries
3. Tracheal rings (cartilage)
4. Serous pericardium = visceral pleura

Question 24

What does the parietal layer become?

Answer 24

Parietal pleura

Question 25

What does the serous pericardium come from?

Answer 25

visceral layer