下列有关基因突变的叙述中,错误的是[ ]
A.基因突变在生物界中广泛存在
B.基因突变的突变率很低
C.基因A可突变为基因a1、a2、b3等
D.基因突变可以产生新的基因
答案:C
联系下文内容,完成短文。
My name is Jack. I 1._____ in London. I am tall. I 2.______ brown hair. I like 3._____.
I run fast. I have many friends. Look, this is Jenny. She 4._____ dancing. She 5._____ beautifully.
That is Ben. He likes running,too,but he does 6._____ run fast. He runs slowly. Betty is a good
girl. She likes PE. She 7._____ high, Tim speaks 8._____. We all help each other
关于抗癫痫药的联合用药错误的是()
A.两种单药治疗无效患者
B.有多种类型发作
C.针对药物的不良反应
D.不宜合用化学结构相同的药物
E.尽量选用副作用相同的药物合用