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
Trees in rainforests have broad leaves. The advantage is______.
Trees in rainforests have broad leaves. The advantage is______.
admin
2010-07-06
31
问题
Trees in rainforests have broad leaves. The advantage is______.
Plants are adapted to the climate they live in for the most part. Trees in rainforests have broad leaves, shaped to encourage the heavy rain to run off the leaves. The large leaves encourage transpiration so the plants don’t overheat. In very dry climates plants may develop an ability to store water, such as the cactus, which also has its leaves reduced into tiny spines which reduce transpiration to almost nothing so its precious water is conserved. At the first sign of drought, plants close their leaf pores to prevent wilting and slowing down growth so that they need less water. Coniferous plants also have small spiky leaves so that they don’t lose too much water during the frozen winters. Grasses roll their leaves into tubes to protect their leaf pores from the drying effect of the wind. Tropical air plants have moisture sensitive plugs attached to their leaf pores which are pulled down over the pores, sealing them to hold in moisture, by the contraction of the stalks in dry weather.
Plants are affected by strong winds which make them grow thicker and more stunted stems to strengthen and prevent themselves from being blown over. A special sort of strong wood called "reaction wood" grows on the leeward side of tile wind. Plants are also susceptible to waterlogging and freezing and many plants have developed complex mechanisms and adaptations to protect themselves from disasters.
选项
A、to accept more sun light
B、to encourage the heavy rain to run off the leaves
C、to shade their roots
D、to hide their trunk
答案
B
解析
转载请注明原文地址:https://kaotiyun.com/show/I1Dd777K
本试题收录于:
公共英语四级笔试题库公共英语(PETS)分类
0
公共英语四级笔试
公共英语(PETS)
相关试题推荐
YouwillhearaninterviewwithMikeRowe,hostoftheAmericanTVshowDirtyJobs.Asyoulisten,answerthequestionsorcompl
YouwillhearaninterviewwithMikeRowe,hostoftheAmericanTVshowDirtyJobs.Asyoulisten,answerthequestionsorcompl
TodayTVaudiencesallovertheworldareaccustomedtothesightofAmericanastronautsintip-topcondition,withfairhair,c
Women’smindsworkdifferentlyfrommen’s.Atleast,thatiswhatmostmenareconvincedof.Psychologistsviewthesubjectei
Youwillreadaquestionwhichsays,"Whichisabettersourceofnews—newspaperorTV?"Writeanarticleforthenewspaper
Allinternationalchainschoolsteachmanydifferentlanguages.
Allinternationalchainschoolsteachmanydifferentlanguages.
Allinternationalchainschoolsteachmanydifferentlanguages.
Apsychologicalissuethatbegantobediscussedinthe1950swasthequestionofthemostappropriateageforsecondlanguagel
Ithasbeennecessarytoreferrepeatedlytotheeffectsofthetwoworldwarsinpromotingallkindsofinnovation.Itshouldb
随机试题
在工作设计中,工作扩大化属于()
ProfessorLi,manystudentswanttoseeyou______theywaithereoroutside!
微分方程y"=x+sinx的通解是()(C1、C2为任意常数)。
下列各项中,在我国属于必须由注册会计师承办的业务是()。
企业常常会使用SWOT(即内部的优势和劣势以及外部的机会与威胁)分析来制定战略,其中属于战略威胁的有()。
下列证照中,应按“权利、许可证照”税目征收印花税的有()。
导游常用的目光应是()。
根据以下资料,回答问题。某市2015年全年粮食总产量4.16万吨,同比下降2.3%;甘蔗产量0.57万吨,下降23.6%;油料产量0.12万吨,增长32.4%;蔬菜产量15.79万吨,下降3.4%;水果产量7.84万吨,增长7.4%。全
关于法律关系主体的权利和义务与作为法律规则内容的权利和义务,的是()。
Moresurprising,perhaps,thanthecurrentdifficultiesoftraditionalmarriageisthefactthatmarriageitselfisaliveand【C1
最新回复
(
0
)