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 the terrible climate of a desert, for these are regions where the annual ra
Plants in Desert Only special plants can survive the terrible climate of a desert, for these are regions where the annual ra
admin
2014-05-13
43
问题
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 °C . 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 that 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 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 that 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 short time. The small shoot system, on the other hand, considerably limits water loss by evaporation(蒸发).
Another feature of many 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.
The theme of the second last paragraph is why the perennials can survive as plants for several years.
选项
A、Right
B、Wrong
C、Not mentioned
答案
A
解析
倒数第二段的主题句是第一句,讲述的主要是沙漠多年生植物能生存的原因。题干表述正确,所以选择A项。
转载请注明原文地址:https://kaotiyun.com/show/ydQd777K
本试题收录于:
职称英语理工类B级题库职称英语分类
0
职称英语理工类B级
职称英语
相关试题推荐
CollegeNightOwlsHaveLowerGradesCollegestudentswhoaremorningpeopletendtogetbettergradesthanthosewhoareni
NaturalMedicinesSinceearliestdays,humanshaveusedsomekindsofmedicines.Weknowthisbecausehumanshavesurvived.
NaturalMedicinesSinceearliestdays,humanshaveusedsomekindsofmedicines.Weknowthisbecausehumanshavesurvived.
ChestCompressions:MostImportantofCPRCardiopulmonaryresuscitation,orCPR,cansavethelifeofsomeonewhoseheartha
Inprevioustimes,whenfreshmeatwasinadequate,pigeonswerekeptbymanyhouseholdsasasourceoffood.
Accordingtothepassage,apersonsufferingfromcancerwillAccordingtotheNewYorkTimes’report,acombinationoftwonew
MediaandCurrentEventsThemediacanimpactcurrentevents.AsagraduatestudentatBerkeleyinthe1960s,Iremembere
MediaandCurrentEventsThemediacanimpactcurrentevents.AsagraduatestudentatBerkeleyinthe1960s,Iremembere
TheBuildingofthePyramidsTheoldeststonebuildingsintheworldarethepyramids.(46)Thereareovereightyofthem
ExposuretotheSuncanacceleratetheageingprocess.
随机试题
设袋中有10个球,其中6个白球,4个黄球,从中任取2个球(设每个球取到的可能性相同),则取出的2个球是1个白球、1个黄球的概率P=_______.
生理功能表现为气机升降关系的脏腑是
治疗火热上炎,口舌生疮,咽喉肿痛,大便秘结者,宜选用
检验检测机构及其人员应当接受安全生产监督管理部门或者()的监督检查。
简单商品流通和发达商品流通的区别有()。
2020年1月,甲公司将闲置厂房出租给乙公司,合同约定每月租金2500元,租期未定。签订合同时,预收租金5000元,双方已按定额贴花。5月底合同解除,甲公司收到乙公司补交租金7500元。甲公司5月份应补缴印花税()元。
实验研究的设计好坏直接影响研究的结果,好的设计有一定标准,这些标准除了包括“是否回答研究主题、是否可有效测量假设”,还包括的指标有()。
根尖片投照上颌单尖牙时,X线片通过投照侧为何解剖标志()。
Whatdoesthehamburgersayaboutourmodemfoodeconomy?Alot,actually.OverthepastseveralyearsWaldoJaquithintendedto
I’mcertainDavid’stoldyouhisbusinesstroubles.______,it’snosecretthatheowesalotofmoneytothebank.
最新回复
(
0
)