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The bryophytes are thalloid structure with two distinct phases in the life cycle. They are the;

  1. The gametophytic generation
  2. The sporophytic generation

The gametophytic phase produces the gametes and each cell of the gametophyte is haploid. The haploid spores are produced during this phase which on germination gives rise to the gametophytic plant body. The gametophyte is an independent plant body which is a thalloid structure. After attaining maturity the gametophyte develops sex organs. The male sex organ is the antheridium and the female sex organ is the archegonium. The antheridium produces biflagellate motile gametes called the antherozoids, whereas the archegonium which produces the non-motile female gametes called the egg. The sexual reproduction is oogamous. The haploid motile antherozoids fuse with the haploid non-motile egg and produce the diploid zygote. The formation of the diploid zygote results in the end of gametophytic generation. i.e. the zygote is the first cell of sporophytic generation. The zygote multiplies and produces the embryo which then develops to the sporophytic plant body. The sporogonium is the sporophytic plant body which is depending on the gametophytic plant body and remains attached with it. The sporophyte has three parts; foot, seta and capsule. The capsule contains the spore mother cells which undergoes meiotic division to produce the haploid spores. The sporophytic generation ends with the formation of spores and the gametophytic generation begins. These spores on germination give rise to gametophytic plant body thus completing the life cycle