题目

Robby was 11 when his mother dropped him off for his first piano lesson. I prefer students to begin at an earlier age. Robby insisted that it had always been his mother’s dream to hear him play the piano, so I took him in as a student. Robby tried and tried while I listened, then I encouraged him and gave him more instructions (指导). But he just did not have any inborn ability. I only saw his mother from a distance. She always waved and smiled, but never came in.  Then one day Robby stopped coming to our lessons. I thought about calling him but I guessed he had decided to try som35. 下图为真核细胞内某基因(N标记)结构示意图,该基因全部碱基中A占20%,下列说法正确的是 A. 该基因一定存在于细胞核内染色体DNA上 B. 该基因的一条核苷酸链中(C+G)/(A+T)为3:2 C. DNA解旋酶只作用于①部位,限制性核酸内切酶只作用于②部位 D. 将该基因置于N培养液中复制3次后,含N的DNA分子占1/8
英语 试题推荐