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【单选题】
Plants in Desert Only special plants can survive the terrible climate of a desert, for these are regions where the annual range of the soil temperature can be over 75℃. Furthermore, during the summer there are few clouds in the sky to protect plants from the sun's ray. Another problem is the fact that there are frequently strong winds which drive small, sharp particles of sand into the plants, tearing and damaging them. The most difficult problem for all forms of plant life, however, is the fact that the entire annual rainfall occurs during a few days or weeks in spring. Grasses and flowers in desert survive from one year to the next by existing through the long, hot, dry season in the form. of seeds. These seeds remain inactive unless the right amount of rain falls. If no rain falls, or if insufficient rain falls, they wait until the next year, or even still the next. Another factor that helps these plants to survive is the fact that their life cycles are short. By the time that the water from the spring rains disappears—just a few weeks after it falls—such plants no longer need any. The perennials have special features which enable them to survive as plants for several years. Thus, nearly all desert perennials have extensive root systems below ground and a small shoot system above ground. The large root network enables the plant to absorb as much water as possible in a short time. The small shoot system, on the other hand, considerably limits water loss by evaporation. Another feature of many desert perennials is that after the rainy season they lose their leaves in preparation for the long, dry season, just as trees in wetter climates lose theirs in preparation for the winter. This reduces their water loss by evaporation during the dry season. Then, in next rainy season, they come fully alive once more, and grow new branches, leaves and flowers, just as the grasses and flowers in desert do. Ordinary plants are unable to survive in the desert mainly because of the changeable weather.
A.
Right
B.
Wrong
C.
Not mentioned
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【简答题】简述法律关系本座说的基本内容。
【单选题】高血压的预防措施中投资少、效益高的预防措施是:
A.
健康教育
B.
早发现
C.
早诊断
D.
早治疗
【简答题】简述法律关系本座说及其意义。
【判断题】候总认为创业的过程中遇到问题的过程同时也是逐渐地解决一些事情的过程。
A.
正确
B.
错误
【单选题】患者,男性,23岁。因头部损伤后,出现球结膜下出血,鼻孔出血且有脑脊液流出,可能为
A.
鼻骨骨折
B.
颅盖骨骨折
C.
颅前窝骨折
D.
颅中窝骨折
E.
颅后窝骨折
【单选题】高血压的预防措施中投资少、效益高的预防措施是:
A.
健康教育
B.
早诊断
C.
早发现
D.
早治疗
E.
康复
【单选题】 以下哪个统一资源定位器的写法是完全正确的
A.
http//www.teach.com\que\que.html
B.
http://www.teach.com\que\que.html
C.
http://www.teach.com/que/que.html
D.
http//www.teach.com/que/que.html
【单选题】下列定义数组中正确的是
A.
char a(20)
B.
int a[5 ];
C.
int b[2]=[1,2];
D.
int c[2,2];
【单选题】常温下,以下哪种物质的导热系数最大( )。
A.
纯铜
B.
空气
C.
D.
钢筋混凝土
【单选题】候总认为遇到问题的时候解决问题的是:()
A.
勇气
B.
善意
C.
智慧
D.
人脉
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