The life cycle of plants consists of the sexual haploid generation (gametophyte), and the asexual, diploid generation (sporophyte). Reproductive organs are formed on the gametophyte. These organs are called male antheridia and female archegonia. Sperm cells formed in antheridia fertilize the egg in the archegonia, resulting in the formation of a diploid zygote. The zygote forms an embryo that develops into a sporophyte. On sporophyte, sporangia develop. In sporangia, meiosis occurs and haploid spores form. A gametophyte develops from a spore, and the cycle starts again. In seed plants, the female gametophyte develops directly on the maternal sporophyte, and the male gametophyte (pollen grain) must be delivered there during pollination. Sporophylls in flower plants are combined into specific reproductive organs - flowers. In seed plants, a specialized structure consisting of several genotypes arises - the seed, which gives rise to a new plant (sporophyte).