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
Only special plants can survive the terrible climate of a desert, for these are regions where the annual range of the soil tempe
Only special plants can survive the terrible climate of a desert, for these are regions where the annual range of the soil tempe
admin
2010-03-22
81
问题
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 mount 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 fall--such plants no longer need ally.
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。本题提问的是shoot system,而非root system,在第三段末句可找到相关信息,由此确定D为正确答案。
转载请注明原文地址:https://kaotiyun.com/show/h4t7777K
0
大学英语四级
相关试题推荐
A、Onlyheroldfriends.B、Onlyherparentsandteachers.C、Hercolleaguesfromwork.D、Newpeopleaswellasoldfriends.DWhat
A、Givehimapresentforhisbirthday.B、Bethereearly.C、Killthetime.D、Remindthemanofthebirthday.AW:Iwantedtobuy
Byusingthenationalroadsystem,onecandrivetoallstatesofAmericawithoutstopping.Itisbelievedthattrucksusingth
A、Helpingtheneedytosurvive.B、Sharingrisksofpossiblelosses.C、Beingcompulsoryinmostcountries.D、Coveringdifferently
A、Unfriendliness.B、Generosity.C、Friendship.D、Strength.DWhatdidthehandprobablysymbolizeinprimitivelife?
__________(要不是有计算机),therewouldnothavebeenman-madesatellitesorrockets.
OverthepastdecadeoneprimaryfunctionoftheWorldBankhasbeen______."civilizedpeople"inthelastparagraphmostprob
A、Thewomandidn’tfinishherproject.B、Themandoesn’thaveacomputer.C、Thewoman’scomputerwasbroken.D、Thewomanhasbou
A、41.B、410.C、14D、214A根据对话中“MontBlanctunnelfireinMarch1999,whichkilled41people”可以推断出此题答案为A。
A、Shedoesn’tneedanewrolloffilmyet.B、Shestillhasn’tfinishedthefirstroll.C、She’llsoonhavetworollstobedevelo
随机试题
我国发票管理规定,发票的存根联及登记簿的保存期限为()
女,34岁。有连续三次晚期自然流产史,现妊娠4+个月,阴道少量出血,下坠感。检查:阴道少量出血,宫颈口开约2cm,宫体前倾,4+个月妊娠大小,无宫缩,附件(一)。孕妇最可能的诊断是
根据《中华人民共和国合同法》规定,下列单位中可以作为保证人的是()。
某企业2009年实现净利润200000元,年初未弥补亏损50000元,另有其他转入20000元,该企业2009年可供分配的利润不正确的有()元。
现有两个投资项目甲和乙,已知甲、乙方案的期望值分别为20%、28%,标准离差分别为40%、55%。那么()。
①欧阳公讳晔,字目华。自为布衣,非其义,不辄受人之遗。少而所与亲旧,后或甚贵,终身不造其门。初为随州推官,治狱之难决者三十六。大洪山奇峰寺聚僧数百人,转运使疑其积物多而僧为奸利,命公往籍之。僧以白金千两馈公,公笑日:“吾安用此?然汝能听我言乎?今岁大凶,汝
李某有一女李霞14岁,系农村某镇初中二年级学生。李某认为女孩上学无用,还不如早点去赚钱。因此李某在2003年暑假将李霞送到邻镇一个体户处打工。开学一周后,学校老师、领导、村干部多次上门家访,李某拒不说明其去向,有时还恶语相报:“孩子读不读书是咱
下列关于医学常识的说法,错误的是:
关系运算中的选择运算是
A、Takeaholiday.B、Haveabusinesstrip.C、Haveameeting.D、GotoNewYork.A对话中间部分,男士表示他想本周与Hebert先生见面,因为Hebert先生下周可能要离开;女士表示
最新回复
(
0
)