01763nas a2200217   4500008004100000245012400041210006900165260001200234300001300246490000800259520103800267653001201305653001701317653001201334653001301346653002101359653001601380100001601396700001701412856011601429       1984                        eng d00aPlastid apportionment and preprophase microtubule bands in monoplastidic root meristem cells of Isoetes and Selaginella0 aPlastid apportionment and preprophase microtubule bands in monop  c1984///  a95 - 1030 v1233 aUltrastructural observations on monoplastidic root tip cells of Isoetes and Selaginella demonstrate two important phenomena associated with preprophasic preparation for mitotic cell division, 1. the preprophase band and 2. precise orientation of the dividing plastid relative to the preprophase band. Both of these phenomena accurately predict the future plane of cell division. The plastid divides in a plane parallel to the spindle and each cell inherits a single plastid which caps the telophase nucleus. When succesive transverse divisions occur, the plastid migrates prior to prophase from a position near an old transverse wall to a lateral position in the cell. The plastid is oriented with its median constriction precisely intersected by the plane of the preprophase band. When a longitudinal division follows a transverse division, the plastid remains in its position adjacent to an old transverse wall where it is bisected by the plane of the longitudinally oriented preprophase band microtubules. © 1984 Springer-Verlag.10aIsoetes10aMicrotubules10aMitosis10aPlastids10aPreprophase Band10aSelaginella1 aBrown, R.C.1 aLemmon, B.E.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-0002906412&partnerID=40&md5=b3cea711cdf0bf1636ca85aff68bf553