During the Anaphase I of meiosis, the pairs of homologous chromosome split up. During this phase sister chromatids of each pair is formed and start moving towards the opposite poles. By the end of anaphase out of each pair of sister chromatids , reaches to the poles of the spindle fibre. During the metaphse of meiosis the chromosomes start their movements and arrange themselves between the poles and the equator of the spindle.
Just say we have a big amount of tryptophan in the sense that it exceeds, tryptophan would act as a co-repressor which prevents synthesis of more enzymes for its production
