Week 5-17: Pseudoglandular Phase

• Begin at around the 9th week of gestational period
• The branching of the lungs increase and bud into more areas.
• Each bud eventually becomes an independent respiratory unit, which is served by a bronchiole, and is surrounded by capillary vessels that bring blood to the lungs for oxygen.

This diagram represents what is occurring in the pseudoglandular phase, where the lungs resemble a gland. At the end of this phase, the precursors of the pneumocytes can be discerned in the respiratory sections as cubic epithelium.

http://www.embryology.ch/anglais/rrespiratory/phasen03.html

ttp://www.livestrong.com/article/163935-fetal-lung-development-stages/