question_answer 37)

  In a flower, if the megaspore mother cell forms megaspores without undergoing meiosis and if one of the megaspores develops into anembryo sac, its nuclei would be (a) haploid                                                                          (b) diploid (c) a few haploid and a few diploid                           (d) with varying ploidy

Answer:

                  (b)In some species, the diploid egg cell is formed without reduction division anddevelops into an embryo        without fertilization.It is an asexual reproduction which occurs in the absence of pollinators or in extremeenvironments. In some species like citrus plants, nucellar cells surrounding the embryosac start dividing and develops into embryos. It occurs in the megaspore mother cell without undergoing meiosis, and producesdiploid embryo sac through mitotic divisions. It helps in the preservation of desirablecharacters for indefinite period. Thus, it can be concluded that apomictic species produce diploid cells. Haploid cellswill be formed during sexual reproduction when cell will undergo meiosis and option 'c'and'd' is not shown by megaspore mother cell.