不属于基因功能的是（ ） A．携带遗传信息 B．携带遗传密码 C．能转录信使RNA
He was about halfway through his meal a familiar voice came to his ears. A.why B.where C.when D.while
—Pick, I did very well in the maths exam last week. —Congratulations, Jim! And I did _____. I got a full mark and 20 extra points. A. no better B. not better
In a recent business magazine article, a president said, Laughter in the workplace is a waste of time. This is a place to do business, not to laugh, some researchers, however, disagree wi
读下图，回答问题。 （1）从耕地状况看，地球的环境人口容量约为__________。 （2）曲线②③告诉我们，科技水平的提高，必然带来人类利用__________在
阅读下面的材料，按照要求作文。 一个牧场主养了许多羊，他的猎户邻居养的凶猛的猎犬常常跳过栅栏袭击牧场里的小羊羔。牧场主几次让猎户把狗关
2009年11月19日，欧盟27国领导人在布鲁塞尔特别首脑会议上推举出了欧盟历史上的首位“总统”和“外长”，这使欧盟在形式上更像一个国家了。这说明
下列除杂的实验方法不正确的是 A．除去CO2中的HCl气体：通过饱和NaHCO3溶液后再干燥气B．除去Na2CO3固体中的NaHCO3：置于
