A pharyngeal groove (or branchial groove, or pharyngeal cleft) is made up of ectoderm unlike its counterpart the pharyngeal pouch on the endodermal side.
The first pharyngeal groove produces the external auditory meatus (ear canal). The rest (2, 3, and 4) are overlapped by the growing second pharyngeal arch, and form the floor of the depression termed the cervical sinus, which opens ventrally, and is finally obliterated.
See also
References
"musom.marshall.edu". Archived from the original on 2009-02-27. Retrieved 2009-05-28. https://web.archive.org/web/20090227080017/http://musom.marshall.edu/anatomy/grosshom/z_devbranc.html ↩
"Archived copy". Archived from the original on 2008-12-17. Retrieved 2008-02-14.{{cite web}}: CS1 maint: archived copy as title (link) https://web.archive.org/web/20081217114417/http://isc.temple.edu/marino/embryology/parch98/ARCHI97/Img016.gif ↩