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 are so common arid quiet that we pay them little mind. What, for instance, should we answer when asked to name the biggest
Trees are so common arid quiet that we pay them little mind. What, for instance, should we answer when asked to name the biggest
admin
2012-10-23
24
问题
Trees are so common arid quiet that we pay them little mind. What, for instance, should we answer when asked to name the biggest living thing Earth has ever seen? Dinosaurs? Blue whales? No, the largest sequoias in northern California weigh more than six blue whales. The tallest redwoods and Australian eucalyptus trees tower more than 300 feet high, three times the length of the greatest dinosaur.【71】Some bristlecone pine trees in the American West are more than 4, 000 years old, seedlings at the time the Egyptians were building the Pyramids. Trees sustain our lives and our planet in a thousand practical ways. This morning at breakfast—in your wood-framed house, on your wooden kitchen table—you might have enjoyed orange juice or a grapefruit. Both come to use from trees. Over your French toast you may have sprinkled cinnamon and nutmeg, the powdered bark and nuts of tropical trees. That quart of maple syrup on your table was boiled down from roughly 10 gallons of sap from a sugar-maple tree.【72】Do you like chocolate, almonds, cola beverages.’? Cocoa beans, almonds and kola nuts are tree products. Frees do more than mule life pleasant; they make life possible. Trees get water through their roots and, primarily through their leaves, they draw carbon dioxide from the air. Then, with the action of sunlight on cells containing chlorophyll and other materials, chemical reactions occur, and oxygen is released.【73】Photosynthesis also produces glucose, a type of sugar. Trees convert some of the glucose to starch, which they use for energy storage. The cellulose fiber we call wood is made of thousands of glucose molecules linked into giant chains that no longer taste sweet.【74】The ancient Greeks, for example, treated pain with a tea made by boiling willow leaves and bark, a tea modern scientists now know contains silicon, a precursor of acetylsalicylic acid—aspirin.【75】More recently, researchers isolated and synthesized the chemical ginkgolide from the tree for use in treating asthma, toxic shock and other ills.
A. For centuries, the Chinese have derived medicines from the ginkgo tree.
B. Through photosynthesis, an acre of trees produces enough oxygen to sustain three humans.
C. As scientists unlock the secrets of trees, they uncover surprising tacts.
D. Trees have always been green machines, producing substances that humans learned to use.
E. You think, at 150 or more years, giant tortoises can live a long time?
F. And the morning newspaper was printed on the processed wood pulp we call paper.
选项
答案
E
解析
转载请注明原文地址:https://kaotiyun.com/show/LW9O777K
0
考博英语
相关试题推荐
Yetthedifferenceintoneandlanguagemuststrikeus,sosoonasitisphilosophythatspeaks:thatchangeshouldremindusth
ForthepeoplewhohavenevertraveledacrosstheAtlanticthevoyageisafantasy.Butforthepeoplewhocrossitfrequentlyo
ForthepeoplewhohavenevertraveledacrosstheAtlanticthevoyageisafantasy.Butforthepeoplewhocrossitfrequentlyo
ForthepeoplewhohavenevertraveledacrosstheAtlanticthevoyageisafantasy.Butforthepeoplewhocrossitfrequentlyo
ForthepeoplewhohavenevertraveledacrosstheAtlanticthevoyageisafantasy.Butforthepeoplewhocrossitfrequentlyo
ForthepeoplewhohavenevertraveledacrosstheAtlanticthevoyageisafantasy.Butforthepeoplewhocrossitfrequentlyo
ForthepeoplewhohavenevertraveledacrosstheAtlanticthevoyageisafantasy.Butforthepeoplewhocrossitfrequentlyo
ForthepeoplewhohavenevertraveledacrosstheAtlanticthevoyageisafantasy.Butforthepeoplewhocrossitfrequentlyo
Thereisanewtypeofsmalladvertisementbecomingincreasinglycommoninnewspaperclassifiedcolumns.Itissometimesplaced
Thereisanewtypeofsmalladvertisementbecomingincreasinglycommoninnewspaperclassifiedcolumns.Itissometimesplaced
随机试题
由患者的家长或家属或他人做出求医决定的求医类型是
硝酸银中毒患者使用的洗胃液是【】
广告的最本质特征是()
为泌尿系感染患儿家长健康宣教,内容正确的是( )。
“阳盛格阴”又称为
患者,男性,40岁。因急性阑尾炎入院,入院后腹痛曾有短暂的缓解,以后又呈持续性加剧,应考虑
某公司主要从事建筑、安装和装饰工程业务,该公司财务会计制度健全,能够如实核算和提供经营情况,并能正确计算应纳税额和如实履行纳税义务。2014年3月有关经营情况如下:(1)取得建筑工程总包结算收入180万元;向分包单位支付工程款45万元。(2)取得建筑工
下列各项中,体现企业业绩衡量股东观的有()。
下列哪个是发明专利申请的申请号?
阅读下面文言文,完成后面各题。元祜①初,山谷②与东坡、钱穆父同游京师宝梵寺。饭罢,山谷作草书数纸,东坡甚称赏之。穆父从旁观曰:“鲁直之字近于俗。”山谷曰:“何故?”穆父曰:“无他,但未见怀素真迹尔。”山谷心颇疑之,自后不肯为人作草书。绍圣③
最新回复
(
0
)