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Le基因是豌豆株高性状的决定性基因,与赤霉素合成有关,其等位基因(符号 T、t)只相差1个核苷酸.隐性基因t产生的酶活性(反应效应)相当于正常酶的 20
1
.下列叙述中正确的是(  )

A:Le基因可直接控制赤霉素合成

B:TT和tt的杂交产生的F1植株具有的酶活性是正常植株中酶活性的120

C:豌豆矮性性状起因于基因Le的缺失

D:用适宜浓度的赤霉素溶液处理tt幼苗,也能使它生长为高植株

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D

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    How to Have a Successful Teenage Life

    Everyone wants to succeed in their life, don't they? Even as a teenager, you can achieve success in your life, it really isn't that hard.____

    Do well in school. No matter how boring it is now, education will help you be a productive member in society. Try your best for excellence in school: listen to the teachers, do your homework, study, and get good grades. Doing so will help you get into a better university, which will enable you to have a bright future.____

    Do good in your community. Volunteering can not only improve your community's status, but could make you happier. Studies show that people who volunteer are less likely to develop depression(抑郁) than people who don't.____.For example, if you love animals, volunteer at an animal shelter. If you love helping the environment, plant trees or pick up litter. When you help others, it will make you feel better about yourself.

    ____.Remember, they're there to help you be the best that you can be. Respect them and value their opinions, even if they annoy you sometimes.____.You don't get to choose your teachers or your family, but you still have to put up with them. Learn how to deal with people now, because when you're an adult, you don't get to choose your boss or your co-workers, so learn how to respect them now.

A. Here are some important points that you may find helpful

B. Be nice to your parents and teachers

C. School sets you up on the right track

D. Find chances to do voluntary work that interests you

E. Keep in mind that they do the things because they care about you

F. Live life fully

G. It will help you pass time and develop your personality