Two types of germ cells, the sexual reproduction cycle, and the double-ring mode of plant developmental program.

In this viewpoint, the usages of terms for progenitor cells to meiosis and gametogenesis are discussed. Terms for 2 types of germ cells, i.e. "diploid germ cells" and "haploid germ cells" were suggested to replace "archesporial cells" and "generative cells," respectively, in plant developmental research. This suggestion was based on 2 newly proposed concepts, the "sexual reproduction cycle" for eukaryotes, and a "double-ring mode" of plant developmental program.