question_answer 18)

At which stage of meiosis does the genetic constitution of gametes is finally decided (a) Metaphase-I                      (b) Anaphase-II         (c) Metaphase-II                  (d) Anaphase-I

Answer:

                (d) The genetic constitute of gametes is finally decided at the anaphase-1 after which each cell receives half the chromosome numbe.r i.e., from '2n' in parent cell it changes to 'n' in daughter cells. During this phase, the two homologou of each chromosome pair separate and move toward opposite poles drawn by microtubule of the spindle apparatus. These are separated further by anaphase-II, wherein sister chromatids of each chromosome separate and move toward opposite poles. It connot be metaphase-1 or metaphase-II because during these stages. The chromosomes or chromatids, merely " arrange themselves at the metaphasic plate.