The Mosses are the non-vascular plants that were developed from the aquatic plants and the ferns are the vascular plants which developed from the bryophytes.
Their life cycle shows alternation of generation and is largely dependent on the water for reproduction mainly fertilization or fusion of gametes.
The male gametes produced in these plant groups are haploid and are released in water which fuses in water with female gamete which is distinct from the higher plant groups gymnosperms and angiosperms where fertilization is mediated by mostly the wind or insects.
A full set of sister chromatids is created during the synthesis (S) phase of interphase, when all the chromosomes in a cell are replicated. The two sister chromatids are separated from each other into two different cells during mitosis or during the second division of meiosis.
