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Carnegie Stage   Figure

Edge of a pronucleus

Edge of a pronucleus

High power TEM of the edge of a pronucleus (Pn) of a stage 1b embryo in vitro, 24 hours post-insemination (original magnification x24,800). Shown are pores in the pronuclear membrane (PnM), an intrapronuclear annulate lamella (IAL) and a nucleolus (N). The pronuclear membrane is very similar to the intrapronuclear annulate membrane.

From: Soupart and Strong, 1974.Reproduced with permission of the American Society for Reproductive Medicine


Keywords: intrapronuclear annulate lamella, intrapronuclear annulate membrane, nucleolus, pronuclear membrane, pronucleus, stage 1b embryo


Source: The Virtual Human Embryo.