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
What is the focus of the passage?
What is the focus of the passage?
admin
2013-05-11
19
问题
What is the focus of the passage?
Scientists have discovered more details about how plants use water. Their findings could help to engineer plants that grow better and more effectively in conditions with higher levels of carbon dioxide. Plants naturally take in carbon dioxide they need for photosynthesis, the process of changing light energy to chemical energy. The carbon dioxide enters the plants through tiny holes or pores on the surface of leaves. However, each time a plant takes in one molecule of carbon dioxide gas, it loses hundreds of water molecules. Scientists say plants lose ninety-five percent of the water they take in through these pores. Some plants’ pores can tighten to save water during conditions of high carbon dioxide. Other plants are not able to do this as well. Now, scientists know how these tiny pores tighten in plants. They identify proteins that control the tightening of a plant’s pores. The proteins are enzymes called carbonic anhydrates. They believe the enzymes could be changed in some plants to increase their ability to store water. Changing plants to save more water will not affect plant growth. This method might be used to help engineer food crops that are resistant to extremely dry conditions. It could help farmers meet a growing demand for food as water supplies decrease.
选项
A、Carbon dioxide.
B、Chemical energy.
C、Molecule.
D、Proteins.
答案
D
解析
细节题。植物利用水的关键是一种蛋白质。
转载请注明原文地址:https://kaotiyun.com/show/YFQK777K
0
专业英语四级
相关试题推荐
Shewasatthe______ofhercareerwhenshewasbadlyinjuredinthecaraccident.
TheartistDorotheaTanninghasdiedinNewYorkaged101.Shewasthelastlivingmemberofthesurrealistmovement,whosecirc
Whichjobwillinvolvesupervisingworkersusingdangerousequipment?
Aconventionalteacher’slicenseusuallyrequiresauniversitydegreeineducationplusanunpaidtermofpracticeteaching.Thi
Archaeologyasaprofessionfacestwomajorproblems.First,itisthepoorestofthepoor.Onlypaltrysumsareavailablefore
Therearemanykindsofsyntheticmaterials,_____plasticsarethemostcommon.
Mysistersaidthatshewouldworkouttheproblemherself_____askmybrotherforhelp.
DoyouknowAlexander’sbrother?Heis______thanAlexander.
"Howdarkyourbrother’shairis!""It’s_____minewhenIwasathisage."
In"howmanypairsofshoesshouldyouandyourbrotherbring?","howmanypairsofshoes"is______.
随机试题
患者,女,35岁,2天前开始腹痛,先上腹后脐周,有阵发性加剧,伴恶心、呕吐2次胃内容物,腹泻3~5次/日,稀便。查体:体温37.5℃,下腹中部压痛,轻度肌紧张,肠鸣音活跃。化验血WBC12.5×109/L,大便常规WBC2~40腹部X线平片未见膈下游离气体
能量代谢
李某,女,32岁,第一胎,孕42周,为待产而入院。平素月经规律,5/28~30天,停经35天尿妊娠试验阳性,孕4个月自觉胎动,间断产前检查,未见异常。身高165cm,BP110/70mmHg,P90次/分钟,一般情况好,心肺未发现异常。产科检查:宫高36
治疗冠心病心绞痛气阴两虚证,可采用的是
疲劳分为肌肉疲劳和精神疲劳。下列措施中,不属于消除精神疲劳的是()。
对外国企业常驻代表机构采用的征税办法包括()。
下面关于金融工具和金融市场叙述错误的是()。
下列词语的书写及画线字的注音全都正确的一项是()。
为什么说宪法的效力和修改程序不同于一般法律?
战争:活动:武器
最新回复
(
0
)