题目

My grandfather once said, “To know yourself, you have to know those who came before you.” He didn’t just say those words; he_______by them. In 1996, my grandfather moved to the United States to care for me and my sister. The decision to leave behind 65 years of family relationships was_______. And he was forced to fit his entire life into two suitcases---one with clothes and books; the other with the_______of long-lost relatives. As we looked through the photos, I saw his face_______with a strong desire to return to those happy times.Some of the photographs were from the nineteenth centu下图A、B是某种雌性动物细胞分裂示意图，C表示该动物细胞分裂时期核DNA数量变化曲线，请据图回答：（1）A细胞所处时期的重要特征是 。（2）B细胞中染色体①与②的分离发生在C图的 阶段，染色体①上基因D与突变基因d的分离发生在C图的 阶段。（3）若图B细胞分裂完成后形成了基因型为DdA的子细胞，其可能的原因是 、 。（4）D图坐标中染色体数与核DNA数之比y1和y2依次为 、 。