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问题 单项选择题

数学中常常能折射出人生智慧。有人将“1.01365≈37.8”和“1.02365≈1377.4”这两个等式解读为：只比你努力一点的人，其实已经甩你太远。这蕴含的哲学道理是（）

A.质变为新的量变开辟道路，在新质的基础上不断发展

B.在量变达到一定程度时，必须要抓住时机才能促成质变

C.没有量的积累就不会有质变的发生，必须重视量的积累

D.要保持事物性质的稳定，就必须把量变控制在一定限度内

答案

参考答案：C

阅读理解
阅读理解。
     Different types of maps have different uses.
Tourist maps, for example, have signs (标志) to
show places of interest in an area. When tourists
read these maps, it is easy for them to find where
to go and what to see in a place and it is easy for
them to go and find their ways to these places.
    Road maps show large areas so that people can
plan long journeys. Different types of roads are
given different numbers. For example, if you want
to go to Wood Green, you just follow No. 621
Road and keep looking at the road signs.
    Distribution maps (分布图) use colors or signs to
show facts about an area. For example, where
different languages are spoken, how many people
live in an area, how cold and hot some places are,
or whether a place is short of water.
     Some maps, such as railway maps, use straight
lines to show everything. This is easy for people
to read. Trains are fast. People don't have to think
about small places they go past. They just need to
know the two ends of their trips.
1. Jim wants to visit some places of interest. Which map does he need most?
A. A road map.
B. A tourist map.
C. A distribution map.
D. A railway map.
2. How can you tell different roads on Road maps?
A. By finding the numbers.
B. By using different colors.
C. By using straight lines.
D. By looking at the road signs.
3. Which of the following can Distribution maps tell us?
A. How to get to Germany.
B. How to plan a long journey.
C. Which place is short of water.
D. Where a famous museum is.
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单项选择题

用纯合的二倍体水稻品种高秆抗锈病（DDTT）和矮秆不抗锈病（ddtt）进行育种时，一种方法是杂交得到Fl，Fl再自交得F2；另一种方法是用F1的花药进行离体培养，再用秋水仙素处理幼苗得到相应植株。下列叙述正确的是（）

A.前一种方法依据的原理是基因重组

B.后一种方法依据的原理是染色体结构变异

C.前一种方法所得F2中的重组类型占5/8

D.后一种方法所得的植株中可用于生产的类型比例为2/3
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