问题 单项选择题 A1/A2型题

下列哪项是基因表达调控的主要环节?()

A.翻译开始

B.基因活化与转录起始

C.转录后转运

D.转录后加工

E.翻译后加工

答案

参考答案:B

解析:基因表达调控可见于从基因激活到蛋白质合成的各个阶段,包括转录水平(基因激活及转录起始)、转录后水平(加工及转运)、翻译水平及翻译后水平的调控,但以转录水平的基因表达调控最重要,尤其是转录起始。

问答题 计算题
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Everybody has had at least one experience from which he knows the meaning of life. This time, which took place several years ago, but seems as if it just happened.

He took the shirt and put it on bed, with the other clothes we were taking to the funeral. Then he closed the drawer and turned to me, “Don’t ever save anything for a special occasion. Every day you’re alive is a special occasion.”

I’m thinking about his words, and they’ve changed the way I live my life. I’m spending more time with my family and friends and less time in committee meetings. Whenever possible, life should be a kind of experience to enjoy, not to suffer. “Someday”and “one of these days”are losing their importance on my vocabulary. If it’s worth seeing or hearing or doing, I want to see and hear and do it now.

Ever since that day, I have been trying very hard not to put off, hold back or save anything that would add laughter and color to our lives. Every morning when I open my eyes, I tell myself that every day, every minute, every breath, truly is a gift. So cherish every day and find the true meaning of your life.

小题1:Why did Jan buy the beautiful skirt but didn’t wear it?

A.She waited for a special occasion to wear it on.

B.She wanted to keep it for someone else.

C.She saved it till she grew up.

D.She would give it to herself as a gift some day.小题2:What does the underlined word “cherish” mean?

A.Treasure.

B.Waste.

C.Own.

D.Save小题3:What does the author write this passage for?

A.To show how to make good use of everyday in life.

B.To explain the true meaning of his brother-in-law’s words.

C.To tell people to cherish every day and find the meaning of life.

D.To encourage people to waste time and enjoy themselves in life.小题4:What’s the best title for this passage?

A.Every Day IS a Gift

B.My Sister Jan

C.What Is the Meaningful Life like

D.The Most Important Time in Your Life