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
Too much metal in the soil is considered pollution. Yet too little metal in a person’s diet can cause health problems. An Americ
Too much metal in the soil is considered pollution. Yet too little metal in a person’s diet can cause health problems. An Americ
admin
2012-04-01
38
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://kaotiyun.com/show/xMlK777K
本试题收录于:
大学英语三级A级题库大学英语三级分类
0
大学英语三级A级
大学英语三级
相关试题推荐
ThatkindofpersonisanythingbutaMarxist.
Hemakeslittleofwalkingfiftykilometersinaday,
Howdidthedoctorfeelwhenthefarmersaid"thereIamagain"?Thedoctorwasalittle______
WhatdoAmericansliketodo?Americansliketolaughand______.
Whatdotheyensureinthelegaltranslation?Whoisthebestpersontotranslatecontracts?
Legaltranslationisoneofthelargestareasofourbusiness.Itstandstoreasonthatanybusinesspersonorindividualmustfu
随机试题
试回答视频传输通道主要指标相关问题。微分增益对图像质量的影响()。
WhatareHenryCountyresidentsaskedtodo?
有关平均寿命的描述,不正确的是
合成类抗结核的药物为( )。结构中有环丙基的药物为( )。
注浆材料应具有固结收缩小,良好的()和化学稳定性。
随机变量的方差可以描述随机变量偏离其期望值的程度,而标准差是对随机变量不确定程度进行刻画的一种常用指标。()
旅游团在一地的旅游全部结束并前往机场,地陪()可以离开机场。
当事人逾期无正当理由不履行行政处罚决定的,作出行政处罚决定的行政机关可以采取下列措施()。
【B1】【B9】
Teachersneedtobeawareoftheemotional,intellectual,andphysicalchangesthatyoungadultsexperience.Andtheyalsoneed
最新回复
(
0
)