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
1 While everybody enjoys fresh cut flowers around their house, few people know how to keep them for as long as possible. This m
1 While everybody enjoys fresh cut flowers around their house, few people know how to keep them for as long as possible. This m
admin
2011-01-22
72
问题
1 While everybody enjoys fresh cut flowers around their house, few people know how to keep them for as long as possible. This may be done by keeping in mind a few simple facts.
2 An important thing to remember about cut flowers is that they are sensitive to temperature. For example, studies have shown that cut carnations(康乃馨) retain their freshness eight times longer when kept at 12℃ than when kept at 26℃. Keeping freshly harvested flowers at the right temperatures is probably the most important aspect of flower care.
3 Flowers are not intended by nature to live very long. Their biological purpose is simply to attract birds or insects, such as bees, for pollination(授粉). After that, they quickly dry up and die. The process by which flowers consume oxygen and produce carbon dioxide(二氧化碳), called respiration(呼吸), generates the energy the flower needs to give the flower its shape and color. The making of seeds also depends on this energy. While all living things respire, flowers have a high level of respiration. A result of all this respiration is heat, and for flowers the level of heat relative to the mass of the flower is very high. Respiration also brings about the eventual death of the flower. Thus the greater the level of respiration, the sooner the flower dies.
4 How, then, to control the rate at which flowers die? By controlling respiration. How is respiration controlled? By controlling temperature. We know that respiration produces heat, but the reverse is also true. Thus by maintaining low temperatures, respiration is reduced and the cut flower will age more slowly.
5 Another vital factor in keeping cut flowers is the quality of the water in which they are placed. Flowers find it difficult to "drink" water that is dirty or otherwise polluted. Even when water looks and smells clean, it almost certainly contains harmful substances that can endanger the flowers. To rid the water of these unwanted substances, household chlorine bleach (含氯漂白剂)can be used in small quantities. It is recommended that 15 drops of chlorine bleach( at 4% solution)be added to each liter of water. The water and solution should also be replaced each day.
A.Control of Respiration
B.Beauty of Fresh Cut Flowers
C.Role of Respiration
D.Most Important Aspect of Flower Care
E. Need for Clean Water
F. Ways of Stopping Respiration
Paragraph 5 ______.
选项
答案
E
解析
第五段开头一句是中心句,这一段主要讲的是水的条件对切花的作用,所以应该选E。
转载请注明原文地址:https://kaotiyun.com/show/BjUd777K
本试题收录于:
职称英语综合类A级题库职称英语分类
0
职称英语综合类A级
职称英语
相关试题推荐
A.hedidnotobservethesuncarefullyenoughB.hecouldnotseeitscurveC.thesun,themoonandthestarsseemedtomovea
Howeverbadthesituationis.themajorityisunwillingtoriskchange.
EarlyUnitedStatesReinterpretedbyBernardBailynBernardBailynhasrecentlyreinterpretedtheearlyhistoryoftheUnite
OfallthechangesthathavetakenplaceinEnglish-languagenewspapersduringthepastquarter-century,perhapsthemostfar-re
ForecastingMethodsThereareseveraldifferentmethodsthatcanbeusedtocreateaforecast.Themethodforecasterchooses
FewFactsaboutSingapore1.SingaporeisanindependentcitystateinsoutheasternAsia,consistingofonemajorisland—the
Whohadthegreatestinfluenceonpeoplewhobecameobese?Whichofthefollowingstatementaboutafriend’sinfluenceisfalse
AIftheGardeners’argumentwassoundBbecauseshewasclevererthanotherchimpsCwhenshewantedtoeatDwhileshewasat
Theunionrepresentativeputacrossherargumentveryeffectively.
Weelicitedtruthbydiscussion.
随机试题
支付结算的票据是指支票、银行汇票、银行本票和()
下列关于作业治疗活动特点描述不正确的是
牛股膝关节特有的结构是
本案应当以谁为被告?设双方当事人在合同中约定:“如果产生纠纷,只能向原告住所地法院起诉。”包头东河区人民法院受理了原告的起诉后,认为原告住所地已经归属于包头市青山区,故包头青山区人民法院有管辖权,遂将案件移送给青山区人民法院。青山区人民法院认为当事人双
栅格结构与矢量结构相比较()。
配送是短距离小批量多品种的送货服务,运输是长距离,大家物资的运输,这是它们在()方面的区别。
如果用一个关键词来对当今的社会文化现状及其发展趋向作出概括的话,那就是“多元”。网络热词的走热,正是这种社会的多元性、文化的包容性的结果。而网络热词本身也是多元的:从内容来说,既有针砭时弊的,也有弘扬正气的,既可直指国计民生的大事,也不排斥细枝末节的小事;
在关系代数中对传统的集合运算要求参与运算的关系(20)。
以下关于过程及过程参数的描述中,错误的是( )。
"Artdoesnotsolveproblems,butmakesusawareoftheirexistence,"sculptorMagdalenaAbakanowiczhassaid.Artseducation,
最新回复
(
0
)