问题 单项选择题

为了形象而概括地反映DNA分子结构的共同特征,生物小组最好采取的方法是()

A.建立概念模型

B.电子显微镜观察

C.建立数学模型

D.建立物理模型

答案

参考答案:D

写作题

仔细观察课文插图中阿切尔的动作、神态,把下面这段话补写完整。

           阿切尔被那个人的举动吸引住了。你看他                                                                                    

                                                                                                                                                              

                                                                                                                                                              

                                                                                                                                                               

                                                                                                                                                               

单项选择题