Name three groups of plants that bear archegonia. Briefly describe the life cycle of any one of them.

Explanation

Bryophytes, Pteridophytes and Gymnosperms are the three groups of plants that bear archegonia. The plant body in bryophytes is haploid. It produces gametes hence it is called gametophyte. The sex organs are multicellular, Jacketed and stalked. Antherediym, which is the male sex organ produces biflagellate antherozoids. Archegonium, the female sex organ, which is flask shaped, produces a small egg. The antherozoids are released into water where they come in contact with archegonium. One antherozoid fuses with the egg to produce the zygote. This is called zooidogamous oogamy. Zygote produce a multicellular body called sporophyte. It is attached to the photosynthetic gemetophyte and extracts nourishment from it.
Some cells of the sporophyte, called spore mother cells undergo reduction division to produce Haploid spores. These spores germinate to produce gametophyte. Bryophytes show alternation of generations (because gametophytic and sporophytic bodies are different) and life cycle is Haplo-diplontic type.