title: Role for differential cell proliferation in perforation and rupture of chick pharyngeal closing plates.
abstract: Patterns of cell proliferation show two distinct domains around avian pharyngeal closing plates as they form, perforate, and rupture. Pouch endoderm and groove ectoderm are in one domain showing 81-86% proliferation, which suggests relatively rapid growth. Cells in epithelia that comprise the pharyngeal closing plates contiguous with pouch and groove epithelia are vital but are dividing at a significantly lower percentage (62-64%). This phenomenon is similar to the lag in growth reported for cells in the oral membrane around the time of rupture (Miller and Olcott, 1989: Anat. Rec., 223:204-208), is consistent with Waterman's suggestion (1985: Anat. Rec., 211:450-457) that cellular reorganization, rather than massive degeneration, is a major mechanism of initial perforation, and suggests that differential growth is a contributor to performation and rupture of chick pharyngeal closing plates.
authors.affiliation: Department of Biology, Hamilton College, Clinton, New York 13323.
authors.forename: S A
authors.initials: SA
authors.lastname: Miller
authors.forename: A M
authors.initials: AM
authors.lastname: Favale
authors.forename: S J
authors.initials: SJ
authors.lastname: Knohl
mesh_terms: D000818:Animals; D002454:Cell Differentiation / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D002642:Chick Embryo; D004707:Endoderm / Q000166:cytology / Q000502:physiology; D009024:Morphogenesis / Q000502:physiology; D010614:Pharynx / Q000166:cytology* / Q000196:embryology* / Q000502:physiology; D013997:Time Factors