ALTERNATION
OF GENERATION
Life cycle of an organism is a sequence of events that crcur from
birth to death of an organism. In plants, both haploid and diploid
cells can divide by mitosis.
This feature leads to the formation of different plant bodies, i.e.
haploid and diploid. ‘The haploid plant body produces gametes by
mitosis. This plant body represents a gametophyte.
After fertilisation, zygote also divides by mitosis to produce a
diploid sporophytic plant body.
Haploid spores are produced by this plant by meiosis.
These in turn, divide by mitosis to form a haploid plant
once again.
Thus, during the life cycle of any sexually reproducing plant,
there is an alternation of generation between gamete producing
haploid gametophyte and spore producing diploid sporophyte.