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STUDIES ON AMPHIBIAN YOLK : 1. The Ultrastructure of the Yolk Platelet

The yolk platelets of mature eggs and young embryonic cells of all amphibian species studied (Rana pipiens, Triturus pyrrhogaster, Diemictylus viridescens, Rana nigromaculata, and Bufo vulgaris) have a superficial layer of fine particles or fibrils (ca. 50 A in diameter), a central main body with a...

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Detalles Bibliográficos
Autor principal: Karasaki, Shuichi
Formato: Texto
Lenguaje:English
Publicado: The Rockefeller University Press 1963
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2106284/
https://www.ncbi.nlm.nih.gov/pubmed/13962448
Descripción
Sumario:The yolk platelets of mature eggs and young embryonic cells of all amphibian species studied (Rana pipiens, Triturus pyrrhogaster, Diemictylus viridescens, Rana nigromaculata, and Bufo vulgaris) have a superficial layer of fine particles or fibrils (ca. 50 A in diameter), a central main body with a crystalline lattice structure, and an enclosing membrane approximately 70 A in thickness. Electron micrographs of the main body reveal hexagonal net (spacing ca. 70 A), square net (spacing ca. 80 A), and parallel band (spacing from 35 to 100 A but most frequent at ca. 70 A) patterns. The crystalline structure is believed to be a simple hexagonal lattice made of closely packed cylindrical rods. Each rod is estimated to be about 80 A in diameter and 160 A in length.