Splanchnic Mesoderm surrounding the
foregut, supporting structures of the tracheobronchial tree, including muscle
and connective tissues, develop from the mesoderm that surrounds the developing
lung bud. the respiratory bud (lung bud) that developed at the caudal end of
the laryngotracheal diverticulum (week 4) divides into 2 lateral outpouchings
--> called primary bronchial buds.
