Fig. 2. Arabidopsis ovule organization and early embryo development. The green rectangle indicates the part of the ovule shown in Fig. 3. See text for details. a, apical daughter of the zygote; ad, apical embryo domain; b, basal daughter of the zygote; cd, central embryo domain; cc, central cell (blue); c, cotyledons; ec, egg cell (red); hy, hypophysis; in, integuments; pd, protoderm; ram, root apical meristem; sc, synergid cells (yellow); sam, shoot apical meristem. The demarcation line between the apical and central domain of the early embryo is indicated (open arrowheads).