题干

下列关于研究材料、方法及结论的叙述,错误的是(    )

A:孟德尔以豌豆为研究材料,采用人工杂交的方法,发现了基因分离与自由组合定律

B:摩尔根等人以果蝇为研究材料,通过统计后代雌雄个体眼色性状分离比,认同了基因位于染色体上的理论

C:赫尔希与蔡斯以噬菌体和细菌为研究材料,通过同位素示踪技术区分蛋白质与DNA,证明了DNA是遗传物质

D:沃森和克里克以DNA大分子为研究材料,采用X射线衍射的方法,破译了全部密码子

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D

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    When I was seven years old, I got the greatest Christmas gift ever.____Now I realize I actually have the power to be a superhero. I may not able to fly, but I make a difference to someone's life. We all have the power to be a superhero to someone. Here are four ways you can be a real life superhero.

    ____Think about what it is. It could be your support, time, advice, a small gift or a thank-you card. Sometimes, even just the most harmless message can bring someone out of darkness and into the light. It's something that you have to give that can help others.

    Keep yourself healthy.____Look after your body and helping people will be easier. You'll have a clear mind and energy to achieve any task in your way.

    Pick your fight. Every superhero has a battle. It's something that drives them to be the person they are.____It could be anything such as working towards helping reduce the number of homeless people on the street. The fight does not need to be big, but it needs to be powerful.

    Make someone's day. Real life superheroes try to improve the lives of all the people they meet.____You can also try your best to absolutely make someone's day every once in a while. The people who get your help will thank you for it.

A. What's your fight?

B. Stay happy all the time.

C. It was a Batman costume, complete with bell and shoes.

D. Use the things you have to help someone without them.

E. You can't be a superhero if you don't take care of your body.

F. They try their best to turn someone's bad day into a good one.

G. They just want to get up, save the world and forget it ever happened.