选择题：下列关于常染色体和性染色体的叙述，不正确的是( ) A．性染色体与性别决定有关

题目：

下列关于常染色体和性染色体的叙述，不正确的是(　　)

A．性染色体与性别决定有关

B．常染色体与性别决定无关

C．常染色体也存在于性细胞中

D．性染色体只存在于性细胞中

答案：

答案：D

题目分析：人体内每个细胞内有23对染色体；包括22对常染色体和一对性染色体，性别是由性染色体决定的，性染色体包括：X染色体和Y染色体，含有一对X染色体的受精卵发育成女性，而具有一条X染色体和一条Y染色体者则发育成男性，不仅性性别含有性染色体，体细胞中也含有性染色体。

点评：此题为基础题，难度一般，解答时可以从染色体的概念和性染色体的组成方面来分析。

题型：阅读理解

Today just as technology changed the face of industry, farms have undergone an “agricultural revolution”. On the farm of today, machines provide almost all the power.

One of the most important benefits will be the farm computer. A few forward-looking farmers are already using computers to help them run their farms more efficiently. The computers help them keep more accurate records so they can make better decisions on what crops to plant, how much livestock to buy, when to sell their products, and how much profit they can expect. Many computer companies have been developing special computer programs just for farmers. Programs are being written for hog producers, grain farmers, potato farmers, and dairy farmers. In the future, farmers will be able to purchase computer programs made to their needs. Because of the growing importance of computers on the farm, students at agricultural colleges are required to take computer classes in addition to their normal agricultural courses. There can be no doubt that farmers will rely on computers even more in the future. While the old-time farm depended on horse power, and modern farms depend on machine power, farms of the future will depend on computer power.

　　Another technological advance which is still in the experimental stage is the robot, a real “mechanized hired hand” that will be able to move and, in some ways, think like a human being. Agricultural engineers believe that computer-aided robots will make startling changes in farming before the end of the century. Unlike farmers of the present, farmers of the future will find that many day-to-day tasks will be done for them. Scientists are now developing robots that will be able to shear sheep, drive tractors, and harvest fruit. Even complex jobs will be done by robots. For example, in order to milk their cows, farmers must first drive them into the barn, then connect them to the milking machines, watch the machines, and disconnect them when they are finished. In the future, this will all be done by robots. In addition, when the milking is completed, the robots will automatically check to make sure that the milk is pure. The complete mobilization of the farm is far in the future, but engineers expect that some robots will be used before long.

小题1:Which sentence carried the main idea of the whole passage?

A．The first sentence of the first paragraph.

B．The first sentence of the second paragraph.

C．The first sentence of the third paragraph.

D．The last sentence of the second paragraph.小题2: according to the passage, computers can not help farmers decide _______.

A．how much money they can earn from their products

B．whether to plant a certain kind of crop

C．what livestock to raise

D．when to sell their products小题3:Which of the following statements is true?

A．Farmers in the future will depend totally on computers.

B．Both computers and robots have been in use on today’s farms.

C．Farmers mainly use machines on their farms at present.

D．Students at agricultural colleges must take computer classes because they can do nothing without the help of computers on today’s farms.小题4:according to the engineers, _______will be done by robots in the near future.

A．all farm work

B．milking cows

C．most of the farm work

D．some farm work小题5:What is the best title for the whole passage?

A．Computer, Farmers’ Best Friend

B．Farmers in The Future

C．The Agricultural Revolution

D．Computers and Robots

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