题干

病毒是一种精明的生物,其核酸几乎只用于合成宿主无法提供的蛋白质。科学家发现一种能以RNA为模板合成DNA的致癌病毒,推测该病毒最可能含有

A:与DNA复制相关的酶基因  

B:与转录相关的酶基因

C:与逆转录相关的酶基因  

D:与翻译相关的酶基因

上一题 下一题 0.0难度 选择题 更新时间:2017-07-02 12:24:20

答案(点此获取答案解析)

C

同类题4

   The teacher stood before his class and was going to hand out the final exam papers. “I know how 1you have all worked to prepare for this test,” he said. “And because I know you can do it well, I am willing to offer a B to anyone who would 2 not to take the test.
Many students jumped up to 3 the teacher and left the classroom. The teacher looked at the 4 students and said, “Does anyone else want to get a B? This is your last 5.” Two more students decided to go.
   Seven students remained. The teacher then handed out the 6. There were only three sentences typed on the paper: Congratulations! You have just 7 an A in this class. Keep believing in yourself.
   I never had a teacher like that, but I think it is a test 8 any teacher could and should give. Students who are not 9 in what they have learned are B students at best(充其量).
   The same is 10 in real life. The A students are those who believe in what they are doing because they have 11 both successes and failures. They have learned life’s lessons, either from normal education 12 from events in their lives, and have become 13 people.
    Scientists say that by the age of eight, 80% of what we believe about ourselves has already been formed. You are a big kid now, and you 14 that you have some limits (限制). However, there is 15 you can't do or learn or be. Sir Edmund Hillary, the first person to reach the summit of Mount Everest said, “It’s not the mountain we conquer(克服) but ourselves.