首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Plants in Desert Only special plants can survive in the terrible climate of a desert, for these are regions where the annual
Plants in Desert Only special plants can survive in the terrible climate of a desert, for these are regions where the annual
admin
2011-01-06
60
问题
Plants in Desert
Only special plants can survive in 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.
Crasses 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(多年生植物)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 (蒸发)。
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 the 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.
We can learn from the passage that the shoot system of the perennials ______.
选项
A、can help the perennials absorb less of the sun’s ray
B、decides the appearance of the perennials in desert
C、limits the function of the perennials’ branches
D、may prevent the perennials from losing much water
答案
D
解析
细节题。本题的解题的关键是注意题干是关于shoot system的提问,而不是root system,在第三段末句可找到相关信息,并由此可确定D为正确选项。
转载请注明原文地址:https://kaotiyun.com/show/vU1d777K
本试题收录于:
职称英语卫生类C级题库职称英语分类
0
职称英语卫生类C级
职称英语
相关试题推荐
A、 B、 C、 B
Readthefollowingtextanddecidewhichanswerbestfitseachspace.Forquestions26-45,markoneletterA,B,CorDony
Somepeoplebelievethatinternationalsportcreatesgoodwillbetweenthenationsandthatifcountriesplaygamestogetherthey
CarsaccountforhalftheoilconsumedintheU.S.,abouthalftheurbanpollutionandonefourththegreenhousegases.Theyta
Oneoftheconflictsthatateacherfacesrelatestoeconomics.Theteacherisexpectedtobeamodelofdressandappearance,t
Beautyhasalwaysbeenregardedassomethingpraiseworthy.【R1】______Theyhavebettermarriagesandhavemorerespectableoccupat
Beautyhasalwaysbeenregardedassomethingpraiseworthy.【R1】______Theyhavebettermarriagesandhavemorerespectableoccupat
1.Moreandmore,theoperationsofourbusinesses,governments,andfinancialinstitutionsarecontrolledbyinformationthate
CONVERSATION2(Questions5-8)Fred’sjob:【L5】______driver.Yearsfordoingthejob:【L6】______.ProblemsFredhad:troublewith
WhatIsAnthrax?There’sbeenalotoftalkaboutanthraxonthenewslately.Somepeoplearewordedthatanthraxmaybeconn
随机试题
地面水环境预测应考虑水体自净能力不同的各个时段。评价等级为三级时应预测( )的环境影响。
运用市场价值法时,当存在着垄断或价格补贴,应采用( )计算环境影响价值。
《学记》中的“时过然后学,则虽勤苦而难成”,说明教学工作应遵循个体身心发展规律的()。
不可能所有的湖北人都喜欢吃辣椒。以下哪项判断的含义与上述判断最为接近?()
(2015广东乡镇51,2015广东县级以上47)天真:幼稚
亚马孙的河流与丛林、安第斯的山脉、巴塔哥尼亚高原、潘帕斯草原,哪怕仅仅是____________这些神秘野性的地理名词,也能莫名其妙地在心中唤起某种情感,好像即将开始一趟心灵的象征之旅,旅途中“对____________的人生做出一番沉思”。填入画横线部
IDEF1X建模第一阶段(建模规划及准备)的主要工作包括______。①建模目标②建模计划③队伍组织④原始材料的获取A)①②③B)①③④C)②③④D)①②③④
中国和平发展和平发展道路是中国这个世界上最大的发展中国家探索出的一条新型发展道路,随着时间的推移,这条道路已经并将进一步显示出其世界意义。这条道路的成功既需要中国人民坚持不懈努力,也需要外部世界理解和支持。中国和平发展打破了“国强必霸”的大
Inmostdevelopedcountries,smallcorporationspayabout32.5percentoftheirnetincomeintaxes_________largeonespay___
【B1】【B19】
最新回复
(
0
)