INTRAMITOCHONDRIAL YOLK-CRYSTALS OF FROG OOCYTES I. Formation of Yolk-Crystal Inclusions by Mitochondria during Bullfrog Oogenesis
نویسنده
چکیده
Electron microscope examination of thin sections of bullfrog (Rana catesbeiana) ovarian oocytes has shown the presence of mitochondria containing yolk-crystal inclusions in oocytes of all sizes, from 160 to 1500 μ mean diameter . The hexagonally shaped yolk-crystals have major periodicities of 73 .8 f 10.7 A (n = 100) . Several forms of modified mitochondria, observed in the smaller oocytes, may be arranged into a series of structurally intermediate forms between standard oocyte mitochondria and the typical mitochondria with yolk-crystal inclusions . The observation of such intermediate forms is consistent with proposals that the yolk-crystal inclusions arise within a limited portion of the oocyte chondriome by a complex process of mitochondrial differentiation .
منابع مشابه
Intramitochondrial Yolk-crystals of Frog Oocytes
Electron microscope examination of thin sections of bullfrog (Rana catesbeiana) ovarian oocytes has shown the presence of mitochondria containing yolk-crystal inclusions in oocytes of all sizes, from 160 to 1500 micro mean diameter. The hexagonally shaped yolk-crystals have major periodicities of 73.8 +/- 10.7 A (n = 100). Several forms of modified mitochondria, observed in the smaller oocytes,...
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