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Carnegie Stage   Figure

Inner cell mass (embryoblast) and trophoblast

Inner cell mass (embryoblast) and trophoblast

SEM of a stage 3 embryo in vitro resulting from intracytoplasmic sperm injection of the ovum that was cultured for five days (original magnification x500).

Note the inner cell mass (ICM) and trophoblast (T). The zona pellucida was chemically removed.

From: Makabe et al., 2001. Reproduced with permission of the publisher, the Italian Journal of Anatomy & Embryology.


Keywords: inner cell mass (embryoblast), trophoblast, zona pellucida


Source: The Virtual Human Embryo.