Fig. 2. (A-C) Schematic of operations used to isolate partial embryos in these experiments. Ablated cells are shaded. CD half-embryos are shown being isolated at the two-cell (A), four-cell (B) or eight-cell stage (C). In most experiments, the 1c cell was subsequently removed at the eight-cell stage, generating a CD-1c partial embryo (B,C, in box). To isolate analogous AD-1a and BD-1b partial embryos, the appropriate quadrant pairs were removed at the four-cell or eight-cell stage followed by ablation of the 1a or 1b micromere.