题干

“假说—演绎法”是现代科学研究中常用的一种方法,下列属于孟德尔在一对相对性状的杂交实验中发现基因分离定律时的“演绎”过程的是(     )

A:生物的性状是遗传因子决定的

B:由F2出现了“3:1”推测,生物体产生配子时成对遗传因子彼此分离

C:若F1产生配子时成对遗传因子分离,则测交后代会出现两种性状,比例接近1:1

D:若F1产生配子时成对遗传因子分离,则F2中三种基因个体比接近1:2:1

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C

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    Are you ready for your exam?

    So, it's exam time again -have you done the necessary work to get good marks? Sleeping with the textbook under the pillow in the hope that knowledge will be magically absorbed into your brain as you sleep doesn't work. The best strategy is to space your practice out, rather than cram(突击学习)it all together.____!

    In an article, Tom Stafford, a lecturer in psychology and cognitive(认知的) science at the APF--University of Sheffield, advises, “If you organize five hours of study into one hour a day, you'll remember more than if you study for five hours a day.”

    ____—get pen and paper and start working. Students who can test themselves in advance will be better at getting back material from their memory and learning that material in the long run. You should start by reading a textbook using your favorite highlighter(荧光笔)____.Instead of just reading those, you basically try to test yourself on them.

    ____, but if you are still anxious, there's no harm in performing a personal ritual(仪式). In Japan, for example, it seems to be a tradition for students to eat Katsudon before a test.____. The name of the dish reminds people of the word “katsu”, meaning“ winning”. The bottom line is that you need to study, sleep well on the eve of the test, eat a nutritious meal, drink plenty of water and believe that your efforts will pay off. Good luck in your exam.

A. Don't rely on memory alone

B. That means hit the books early

C. Good revision should give you confidence

D. Then make flashcards of all the important concepts

E. They believe they could wash all the knowledge out of their head

F. This is a warm bowl of rice topped with egg and a slice of deep-fried pork

G. In different countries there are always those who swear by their “lucky underwear”