Flexi Says: Plants alternate between diploid sporophyte and haploid gametophyte generations, and between sexual and asexual reproduction. The ability to reproduce both sexually and asexually gives plants the flexibility to adapt to changing environments. Their complex life cycle allows for great variation. The diploid sporophyte has a structure called a sporangium (plural, sporangia) that undergoes meiosis to form haploid spores. A spore develops into a haploid gametophyte. The gametophyte has male or female reproductive organs that undergo mitosis to form haploid gametes (sperm or eggs). Fertilization of gametes produces a diploid zygote. The zygote grows and develops into a mature sporophyte, and the cycle repeats.