问题 填空题

如图是关节模式图,据图回答:

图中1是______,2是______;二者相对的面上有一层3,这是______,具有减少______,缓冲______的作用,属于______组织;4是______,由______组织构成;5是______,内有少量______,是由______分泌的.另外,关节囊外还有______.由图可以看出,关节结构具有既______又______的特点.

答案

据分析可知:图中的1是关节头,2关节窝,;两者构成关节面,关节面上覆盖着一层3关节软骨,关节软骨属于结缔组织,表面光滑,可减少运动时两骨间关节面的摩擦和缓冲运动时的震动,此外,关节囊的内表面能分泌滑液,进入由关节囊和关节面共同围成的密闭腔隙5关节腔,滑液关节软骨,使关节更加灵活.

4是关节囊,由结缔组织构成,包绕着整个关节,把相邻的两骨牢固地联系起来.关节囊及囊内外的韧带使关节具有牢固性.

故答案为:关节头;关节窝;关节软骨;骨与骨之间的摩擦;运动时的震荡;结缔;关节囊;结缔;关节腔;滑液;关节囊内壁;韧带;牢固;灵活.

单项选择题

Some pessimistic experts feel that the automobile is bound to fall into disuse. They see a day in the not-too-distant future when all autos will be abandoned and allowed to rust. Other authorities, however, think the auto is here to stay. They hold that the car will remain a leading means of travel in the foreseeable future.

The motorcar will undoubtedly change significantly over the next 30 years. It should become smaller, safer, and more economical, and should not be powered by the gasoline engine. The car of the future should be far more pollution-free than present types.

Regardless of its power source, the auto in the future will still be the main problem in urban traffic congestion (拥挤). One proposed solution to this problem is the automated highway system.

When the auto enters the highway system, a retractable (可伸缩的) arm will drop from the auto and make contact with a rail, which is similar to those powering subway trains electrically. Once attached to the rail, the car will become electrically powered from the system, and control of the vehicle will pass to a central computer. The computer will then monitor all of the car’s movements.

The driver will use a telephone to dial instructions about his destination into the system. The computer will calculate the best mute, and reserve space for the car all the way to the correct exit from the highway. The driver will then be free to relax and wait for the buzzer (蜂鸣器) that will warn of his coming exit. It is estimated that an automated highway will be able to handle 10,000 vehicles per hour, compared with the 1,400 to 2,000 vehicles that can be carried by a present-day highway.

One significant improvement in the future car will probably be ().

A. its power source

B. its driving system

C. its monitoring system

D. its seating capacity

判断题