在用显微镜观察洋葱鳞片叶表皮细胞临时装片的过程中，下列说法正确的是（ ）
A．观察装片，发现物像的视野的左上方，应将装片向右下方移动
B．所观察到的细胞的放大倍数是目镜的放大倍数与物镜放大倍数之和
C．若在低倍镜下观察到细胞物像模糊，可转动遮光器换成高倍镜进行观察
D．观察洋葱鳞片叶表皮细胞临时装片时可通过开大光圈来增加视野亮度
解；A．显微镜下看到的物像是一个放大的倒像，物像的移动方向和玻片的移动方向相反，观察装片，发现物像的视野的左上方，将物像移到中央就要向右上方移动物象，应将装片向左上方移动．该选项说法错误B．显微镜的放大倍数等于武警放大倍数与目镜放大倍数的乘积，该选项说法错误
C．若在低倍镜下观察到细胞物像模糊，应调节细准焦螺旋使物像清楚．该选项说法错误
D．观察洋葱鳞片叶表皮细胞临时装片时可通过开大光圈来增加视野亮度，该选项说法正确
故选：D
Choose the words or expressions and complete the passage Exam time is the most stressful (最有压力的) period of the year. You’ve worked all the term on your classes and now it’s the time to prove what you have learned. With so much at stake, it is easy to get stressed about your exams. However, with the right amount or hard work and focus you can pass your tests 1! When I was in school, I used to get very stressed over my examinations. So did my friends. Some people stopped eating and others ate too much! Some 2 and others burned themselves out! The most important thing to remember when studying is not to panic! Take the middle path---stay calm, eat healthy food and get your rest. Stressing out and _3___yourself too hard is just as dangerous as not studying enough. A tired, overworked brain is just as useless as a stupid, empty one! So, what do you do? Set aside a time each day for study and a time For __4 . You may have less time to relax than usual, but you still need to let your brain rest for a few moments. Get plenty of sleep. If you are_ 5 , information will not stick in your memory. Finally, eat healthy food that fuels your body and mind. It does no good to look at your exams like the rest of your life 6 them. Instead, just view them as another obstacle (障碍物) you will overcome. You have overcome all kinds of obstacles in your life so far. With the right amount of work and focus, you will pass your examinations with flying colors! High school is right around the corner.
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