21. After fertilization the zygote gives rise to ~ 20 sporocysts. 22. It is not known why some zygotes do not implant. 23. The zygote undergoes repeated mitosis and differentiation to become a diploid organism again. 24. The zygotes of the gametes develop into sporangium, which produces haploid spores. 25. The result of karyogamy is a diploid cell called a zygote or zygospore. 26. As the zygote divides and grows, it does so inside the archegonium. 27. Two gametes fuse to form a zygote which develops into a new sporophyte. 28. The exact cause for the splitting of a zygote or embryo is unknown. 29. Next the zygote forms a macrocyst characterized by a surrounding extracellular cellulose sheath. 30. Within the macrocyst the diploid zygote undergoes meiosis followed by successive mitotic divisions.
