题目

Kids may need to apologize if they do something they know was wrong－like telling a lie or breaking a rule on purpose. When they do something their parents tell them not to do，or they don't do something they are supposed to do，they apologize，too. Grown-ups can apologize，too，to other grown-ups or even to kids. After all，even grown-ups make mistakes sometimes. By apologizing when they're wrong，grown-ups can set a good example and show kids how to do the right thing and apologize when they need to. Saying I'm sorry when you need to is the right thing to do. It does a lot of g下图表示DNA分子结构的片段 (1)请写出图中各结构的名称：①                      ②                      ③                 ④                      ⑤                 (2)下列叙述不正确的是：(      )A．DNA分子的骨架结构使其具有较强的特异性B．正常情况下，该DNA分子中的嘌呤数与嘧啶数相等C．该片段中共包含了8个脱氧核苷酸，4种碱基D．若该片段丢失，并在显微镜下可以直接观察到，这种变异应属于染色体结构变异(3)一个细胞中的某一条染色体上的DNA双链都用15N标记过，在有丝分裂间期利用含14N的脱氧核苷酸作为原料进行复制，复制完成后该染色体的状况是：                            (子代分子中含15N、14N的情况) 。