Week 36-Birth: Alveolar Phase

• Occurs during the 36th week of the gestational age.
• The lung development during this phase is characterized by the growth of bronchioles and air sacs, or alveoli.
• The alveoli allows the gas-exchange tissues of the lungs to expand and make them capable of moving more air into the lungs as the fetus grows.

The diagram above shows that in the alveolar phase, the alveoli form from the terminal endings of the alveolar sacculi and with time, they increase in diameter.

http://www.embryology.ch/anglais/rrespiratory/phasen06.html

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