Fig. 2. CI in N. giraulti. (A) Category 1. Nuclear cycle 2 embryo in which chromosomes were segregated correctly. (B) Category 2. Nuclear cycle 2 embryo in which the paternal genome was not segregated. There are two normal nuclei and one highly condensed nucleus (arrow). (C) Category 3. Nuclear cycle 2 embryo in which the paternal genome had segregated to one daughter nuclear at the end of the previous cycle. There are two normal nuclei and one composite nucleus (arrowhead). (D-F) Category 4. In 83% of giraulti CI embryos, the paternal genome mis-segregates to both daughter nuclei. (D) Nuclear cycle 2, the two nuclei are connected by a chromatin bridge. (E) Nuclear cycle 3, all four nuclear products are connected by chromatin bridges. (F) Several embryos contained one massive nucleus composed of diffuse DNA. (G) Control uninfected embryo at nuclear cycle 9, note nuclei are evenly spaced from each other. (H) The majority of CI embryos arrest development with a few highly condensed nuclei. (I) A few CI embryos reach the syncytial blastoderm stage but notice nuclei are not evenly spaced from neighbors and chromosome fragments are present. Bars, 8 µm (A-F).