Zygote with zona pellucida reaches uterine cavity by-

Ans-B lets revise some imp points:- 1-morula=16 cell stage 2-blastocyst hatching/ZP removal/implantation=5-12 days after fertiization(5-7 days) 3-sequence of reactions is alphabetical=acrosome rxn f/b cortical rxn f/b zona reaction. 4-conceptus reaches uterine cavity in 32cell stage. 5-transvaginal insertion of coceptus 8 cell stage. 6- spermatogenesis is completed in 74 days 7-trophoblast differentiates into cyto and syncytio day 6. 8- ovulation occurs 10-12 hrs before LH PEAK. 9-LH SURRGE occurs 34-36 hrs before ovulation.