Question

When and where does reduction division take place in the life cycle of a liverwort, a moss, a fern, a gymnosperm and an angiosperm?

Answer 1

Key Idea: Reduction Division (Meiosis)

Reduction division (meiosis) is the type of cell division in which the chromosome number is reduced from diploid \((2n)\) to haploid \((n)\). In plant life cycles, meiosis usually occurs in the diploid sporophyte to produce haploid spores, which then give rise to the gametophyte generation.

Answer in Tabular Form

Plant group	When (stage)	Where (exact site)
Liverwort	During formation of spores at the end of sporophyte generation	In spore mother cells inside the capsule of the sporophyte
Moss	During formation of spores at the end of sporophyte generation	In spore mother cells within the capsule (sporangium) of the sporophyte
Fern	During spore formation by the sporophyte	In spore mother cells inside sporangia present on the sporophylls (leaves)
Gymnosperm	During formation of microspores and megaspores in the dominant sporophyte	In microspore mother cells of microsporangia (male cones) and megaspore mother cells of megasporangia (ovules on female cones)
Angiosperm	During formation of microspores (pollen grains) and megaspores (embryo sac initial)	In microspore mother cells of anthers and megaspore mother cell in the ovule (inside ovary)

Compact Point-wise Answer

• Liverwort: Meiosis occurs in spore mother cells inside the capsule of the sporophyte during spore formation.
• Moss: Meiosis occurs in spore mother cells in the capsule (sporangium) of the sporophyte at the time of spore formation.
• Fern: Meiosis occurs in spore mother cells in sporangia borne on the sporophylls (fertile leaves) of the sporophyte to produce spores.
• Gymnosperm: Meiosis occurs in microspore mother cells of microsporangia on microsporophylls (male cones) and in megaspore mother cells of megasporangia (ovules) on megasporophylls (female cones).
• Angiosperm: Meiosis occurs in microspore mother cells of anthers to form pollen grains and in the megaspore mother cell of the ovule in the ovary to form megaspore (leading to the embryo sac).