A 2-day-old infant born at 32 weeks' gestation has had breathing difficulties since birth and is currently on a respirator and 100% oxygen. These difficulties occur because of which one of the following?
The baby has respiratory distress syndrome, caused by an inability to produce surfactant, a hydrophobic molecule that is secreted by the type II cells in the lung and coats the airways, reducing surface tension during contraction and allowing relatively easy expansion of the lung during inhalation. This is due to the lungs not yet producing surfactant, which contains a few proteins and a large amount of dipalmitoyl phosphatidylcholine. Respiratory distress syndrome is not related to insulin or glucagon response by the lung, or the ability of the lung cells to generate energy.
An inability of the lung to contract to exhale
An inability of the lung to expand when taking in air
An inability of the lung to respond to insulin
An inability of the lung to respond to glucagon
Lipids