There are three main categories of life cycles: diploid-dominant, demonstrated by most animals; haploid-dominant, demonstrated by all fungi and some algae; and alternation of generations, demonstrated by plants and… Meiosis and fertilization alternate in sexual life cycles.

However, the ways in which reproductive cells are produced and the timing between meiosis and fertilization vary greatly. The variation introduced into the reproductive cells by meiosis appears to be one of the advantages of sexual reproduction that has made it so successful.

diploid-dominant — a life-cycle type in which the multicellular diploid stage is prevalent. haploid-dominant — a life-cycle type in which the multicellular haploid stage is prevalent. life cycle — the sequence of events in the development of an organism and the production of cells that produce offspring. fertilization — the union of two haploid cells typically from two individual organisms.