Name three groups of plants that bear archegonia. Briefly describe the life cycle of any one of them.
The three groups of plants that bear archegonia are Bryophytes, Pteridophytes, and Gymnosperms.
In pteridophytes, the main plant body is a sporophyte which is differentiated into true root, stem and leaves. These organs possess well-differentiated vascular tissues. The leaves may be small called microphylls as in Selaginella or large called macrophylls as in ferns.
The sporophytes bear sporangia that are subtended by leaf-like appendages called sporophylls. In some cases, sporophylls form distinct compact structures called strobili or cones. The sporangia produce spores by meiosis in spore mother cells.
The spores germinate to form gametophytes which require cool, damp places to grow. The gametophytes bear male and female sex organs called antheridia and archegonia respectively. Water is required for transfer of male gametes to the archegonium where zygote is formed after fertilisation. The zygote then produces a sporophyte, completing the life cycle.
Explanation
The context explicitly mentions that in pteridophytes, gametophytes bear archegonia. Bryophytes have a dominant gametophytic plant body, implying presence of archegonia on their gametophytes. Gymnosperms are the third group mentioned in the context. The life cycle of pteridophytes is described in detail in the context - showing alternation of generations where the sporophyte produces spores that develop into gametophytes, which then produce gametes and after fertilisation form zygote that develops back into sporophyte.