During the third week of embryonic development, two areas of thickened ectoderm, the olfactory areas, appear immediately under the fore-brain in the anterior wall of the stomodeum, one on either side of a region termed the frontonasal prominence (or process).
By the upgrowth of the surrounding parts these areas are converted into pits, the olfactory pits, which indent the frontonasal prominence and divide it into a medial and two lateral nasal processes.
There is some evidence that development involves Sonic hedgehog and Fibroblast growth factor 8.
Famous quotes containing the word prominence:
“Here the term language-game is meant to bring into prominence the fact that the speaking of language is part of an activity, of a form of life.”
—Ludwig Wittgenstein (18891951)