Figure 13

Zygote scoring system of Lan et al. [23]. Zygote Z1 had equal number of nucleoli (between 3 and 7) aligned at the PN junction (A), Z2 had nucleoli equally in number and size equally scattered in both PN (B), Z3 had equal number of nucleoli of equal size in the same PN but with one PN having alignment at the PN junction and the other with scattered nucleoli (C), and Z4 had PN not aligned, grossly different in size or not located in the central part of the zygote (D). Zygotes with unequal number (a difference of more than one nucleolus), and/or size of nucleoli were considered as Z3.