Is a pollen grain a single cell?

sequoianoir

The alternation between diploid and haploid cells or organisms. In most lower plants, up to and including ferns, the gametophyte (haploid) and sporophyte (diploid) generations are separate, independent, free-living plants. In flowering plants, through evolution, the gametophyte generation has become reduced to just a small group of haploid cells, enclosed within the flower and completely supported by the diploid parent plant. In Angiosperms, the male gametophyte generation takes place in the anther. The final product of this generation is the pollen grain. Jan 08 03, 11:51 PM

Anther- The terminal pollen sac of a stamen, inside which pollen grains harboring male gametes form in the flower of an angiosperm. Haploid- The condition of having only one kind of a given type of chromosome. Within the pollen sacs of the anther, numerous microspore mother cells (1) undergo meiosis to produce four haploid microspores (2-3). Within each microspore, a mitotic division results in the formation of two {nuclei;} a thickening of the outer layer also occurs. The result of this process is four pollen grains . http://tidepool.st.usm.edu/crswr/pollengrainform.html Jan 09 03, 12:20 AM