Genetics. A bioassay that can provide a first alert for the presence of genotoxic agents in the air. Meiotic chromosomes of the pollen mother cells of Tradescantia inflorescences are very sensitive to different mutagens. As a result, chromosome aberrations and breakage can occur. The micronuclei (MCN) formed by these damaged chromosomes can be easily detected using a microscop in the early tetrad stage of meiosis.