Exam 12: Development of the Respiratory System and Body Cavities

A medical student is confused when learning that the muscle of the diaphragm is innervated by the phrenic nerves,based on the level of origin of these nerves from the CNS.What is the explanation of how this innervation occurs during embryogenesis?

A mouse exhibiting congenital diaphragmatic hernia was produced by ENU mutagenesis.What gene was mutated in this mouse?

Pulmonary hypoplasia is often associated with which prenatal condition?

A premature baby is not producing sufficient surfactant.What is known to stimulate surfactant synthesis prior to birth?

Transgenic and gene targeting approaches have played important roles in understanding lung development and branching morphogenesis.Using this approach,Fgf signaling was blocked in the developing respiratory tree.What was the outcome of this experiment?

In tissue recombination experiments in culture it has been shown that branching morphogenesis of the lung involves epithelial-mesenchymal interactions.What is the source of the lung epithelium?

Branching of the Drosophila tracheal system involves three genes,Branchless,Breathless,and Sprouty,and orthologs of these genes play similar roles in vertebrate lung development.What would be the expected outcome if Sprouty is inactivated during Drosophila development?

A baby with a severe diaphragmatic hernia with herniation of visceral into the pleural cavity also has other anomalies of the respiratory system.What anomaly is likely to be present?

A premature baby,born at 30 weeks,is suffering from respiratory distress.What stage of lung development would the lungs have reached at the time of delivery?

An embryologist is studying the development of the phrenic nerve in human embryos.He reads that these nerves course through tissues involved in coelom partitioning.What is this tissue?