首页
登录
职称英语
Trees are so common arid quiet that we pay them little mind. What, for insta
Trees are so common arid quiet that we pay them little mind. What, for insta
游客
2025-04-27
35
管理
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. [br]
选项
答案
B
解析
转载请注明原文地址:https://tihaiku.com/zcyy/4055929.html
相关试题推荐
Lindacouldnotrefuse,______sheforesawlittlepleasureinthevisit.A、since
Therewaslittle,ifany,evidencetosubstantiatethegossipand,,therewasl
Bythe1820sintheUnitedStates,whensteamboatswerecommononwesternwa
Theappealtothesensesknownas______isespeciallycommoninpoetry.A、imagin
Treesaresocommonaridquietthatwepaythemlittlemind.What,forinsta
Treesaresocommonaridquietthatwepaythemlittlemind.What,forinsta
Treesaresocommonaridquietthatwepaythemlittlemind.What,forinsta
Certainlynocreatureintheseaisodderthanthecommonseacucumber.All
Certainlynocreatureintheseaisodderthanthecommonseacucumber.All
Thelittlegirlworeaverythincoat.Asuddengustofcoldwindmadeher_____
随机试题
Lookattheplanofthecorrectplace.Forquestions6-10,decidewhichplaceis
[originaltext]Moderator:Goodmorningeveryone,welcometoourseminar.Fir
[originaltext]W:Goodmorning,Mr.Jacob.Iseverythingallright?M:No,it’s
Readthefollowingtext.Choosethebest
回答有关摆式仪试验的测试问题。(4)摆式仪试验的测试步骤为:①调零。②仪器调平。
祛痰剂中常配伍的药物是A.祛湿药 B.清热药 C.补气药 D.收涩药 E
糖尿病静脉血浆葡萄糖值诊断标准是A.随机≥11.1mmol/L或空腹≥7.0mm
借款企业预提银行借款利息属于()。A.流动资产 B.非流动资产 C.流
会计资料移交后,如果发现是移交人员以前会计工作期间内所发生的问题,由()负责。A
建设单位应当自建设工程竣工验收合格之日起( )日内,将竣工验收报告和规划、公安消
最新回复
(
0
)