首页
登录
职称英语
Too much metal in the soil is considered pollution. Yet too little metal in
Too much metal in the soil is considered pollution. Yet too little metal in
游客
2024-07-07
48
管理
问题
Too much metal in the soil is considered pollution. Yet too little metal in a person’s diet can cause health problems. An American scientist says the answer to both problems may be plants that take up large amounts of metal in their tissues.
David Salt is an expert on plants at Purdue University in West Lafayette, Indiana. He is working with plants that store large amounts of metals.
In recent years, scientists have shown interest in using such plants to clean up harmful waste materials. Professor Salt says such plants also could be used to improve people’s diets or even to create foods that fight cancer.
Humans need a number of metals in their diets, including iron and zinc. These metals are needed in very small amounts, however. That is why they are called micronutrients. The lack of micronutrients is blamed for health problems in many developing countries. Children and pregnant women are mostly affected.
Recently, Mr. Salt announced that he has identified and copied the genes from a kind of plant that stores metals in its tissues. He says his study suggests it may be possible to develop plants that contain minerals needed for good health.
For example, the metal selenium is a strong anti-cancer agent. Some wild plants store selenium naturally. Mr. Salt says foods to fight cancer might be created if genes from these plants could be moved into crop plants.
Locoweed, which is a common plant in the western U.S., stores selenium. Professor Salt says it may be possible to create cancer-fighting foods from it. He and scientists from a company called Unicycle Therapies have copied the gene that causes locoweed to take up selenium from the soil.
Many people take pills to add important minerals or vitamins to their diet. However, Mister Salt notes that most selenium products sold in health food stores are of little use. That is because the human body can only take in and use selenium if it is in the right chemical form.
The scientist says his team would like to develop a vegetable crop high in selenium. He wants to create an anti-cancer product in the foods we already eat.
选项
A、clean polluted soil and cure disease like cancer
B、clean up harmful waste materials in soil and improve people’s diet
C、produce large number of micronutrients such as iron and zinc
D、create food with important minerals or vitamins
答案
B
解析
文章首段即讲到美国的一位科学家,即下文中的David Salt,认为这样的植物可以用来解决两方面的问题:净化土壤和促进人类健康。
转载请注明原文地址:https://tihaiku.com/zcyy/3666575.html
相关试题推荐
Toomuchmetalinthesoilisconsideredpollution.Yettoolittlemetalin
Thelittlegirlgavean(extreme)______wonderfulperformancelastnight.extrem
Thatman’srudebehaviormadethelittlegirlso(anger)______thatshethrews
[originaltext]M:WhereisTonythisevening?W:Heisalittleundertheweathe
Themarketingmanagerhaslittleconfidenceintalkingtheboardofdirectorsou
[originaltext]W:CouldyoupleaseturndownyourTValittle?M:Sorry!Areyou
Allthings______,herpaperisofgreatervaluethanmine.A、havingconsideredB
[originaltext]M:Excuseme,haveyouseenmylittlegreydogasyouwerewalkin
Consequently,itiseasytounderstandwhylittlegirlsoftenperformschooltas
Thelittleboy______hisfootseveraltimesinanger.A、jumpedB、stampedC、knock
随机试题
The18thcenturyinEnglishliteratureisanageof______.A、novelB、poemC、pros
Ifit______toomuchtrouble,I’dloveacupofcoffee.A、hadn’tbeenB、isn’tC、
(tell)______thetruth,Idon’tliketheideaatall,Totell说实话,我一点也不喜欢这个主意。动词不
谁能否认海的伟大呢?我爱海,并不仅仅因为她的颜色美丽,和藏在海底那许多有趣的玩意儿,而是爱她的胸襟广阔,化污秽为清洁。她容纳无数的细流,尽管她们的颜色有
LongitudeandLatitudeThemeridiansof
下列关于宏观经济发展目标及其衡量指标说法错误的是()。A.GDP增长率是反应一
学前班幼儿发展的评价主要是通过( )。A.测验 B.评价幼儿学习文化知识、算
《斗牛士之歌》是()中的片段。A.《茶花女》 B.《卡门》 C.《塞维利
在用起重机械应当在每次使用前进行一次()性检查,并做好记录。(A)常规
属于人的稳定的心理特征之一,影响人的心理活动和行为的动力特点是()。A:能力B
最新回复
(
0
)