皮皮学,免费搜题
登录
搜题
【单选题】
'Salty' Rice Plant Boosts Harvests British scientists are breeding a new generation of rice plants that will be able to grow in soil containing salt water. Their work may enable abandoned farms to become productive once more. Tim Flowers and Tony Yeo, from Sussex University's School of Biological Sciences, have spent several years researching how crops, such as rice, could be made to grow in water that has become salty. The pair have recently begun a three-year programme, funded by the Biotechnology and Biological Sciences Research Council, to establish which genes enable some plants to survive salty conditions. The aim is to breed this capability into crops, starting with rice. It is estimated that each year more than 10m hectares(公顷) of agricultural land are lost because salt gets into the soil and stunts(妨碍生长) plants. The problem is caused by several factors. In the tropics, mangroves(红树林) that create swamps(沼泽) and traditionally formed barriers to sea water have been cut down. In the Mediterranean, a series of droughts have caused the water table to drop, allowing sea water to seep(渗透) in. In Latin America, irrigation often causes problems when water is evaporated(蒸发) by the heat, leaving salt deposits behind. Excess salt then enters the plants and prevents them functioning normally. Heavy concentrations of minerals in the plants stop them drawing up the water they need to survive. To overcome these problems, Flowers and Yeo decided to breed rice plants that take in very little slat and store what they do absorb in cells that do not affect the plants' growth. They have started to breed these characteristics into a new rice crop, but it will take about eight harvests before the resulting seeds are ready to be considered for commercial use. Once the characteristics for surviving salty soil are known, Flowers and Yeo will try to breed the appropriate genes into all manners of crops and plants. Land that has been abandoned to nature will then be able to bloom again, providing much needed food in the poorer countries of the world. Which of the following statements about Flowers and Yeo is true?
A.
They are students at Sussex University.
B.
They are rice breeders.
C.
They are husband and wife.
D.
They are colleagues at an institution of higher learning.
拍照语音搜题,微信中搜索"皮皮学"使用
参考答案:
参考解析:
知识点:
.
..
皮皮学刷刷变学霸
举一反三
【单选题】选择滚动轴承配合时,当负荷方向不变时,转动套圏应比固定套圏的配合( ).
A.
B.
C.
相同
D.
松紫
【判断题】网络营销活动可以脱离一般营销环境而独立存在。
A.
正确
B.
错误
【单选题】通过卫星通信连接计算机的新软件产品,假设之前没有开发卫星通信软件的经验,应该选择哪种软件开发模型?
A.
瀑布模型
B.
增量模型
C.
快速原型模型
D.
螺旋模型
【简答题】选择滚动轴承配合时,当负荷方向不变时,转动套圈应比固定套圈的配合( )。A. 4
【单选题】选择滚动轴承配合时.当负荷方向不变时.转动套圈应比固定套圈的配合 。
A.
B.
C.
相同
D.
松紧都可
【单选题】“司马光砸缸”的故事体现的主要是运用了(思维)解决了问题。
A.
直觉行动思维
B.
具体形象思维
C.
常规性思维
D.
创造性思维
【判断题】网络营销活动可以脱离一般营销环境而独立存在
A.
正确
B.
错误
【单选题】用IE访问网页时,一般要等到()才能单击鼠标访问网站里的信息。
A.
鼠标变成闪烁状态时
B.
鼠标依旧是箭头形状时
C.
鼠标变成手形时
D.
鼠标箭头旁边出现一个问号时
【单选题】用IE访问网页时,一般要到 才能单击鼠标访问网站里的信息。
A.
当鼠标变成闪烁状态时
B.
当鼠标依旧是箭头形状时
C.
当鼠标变成手形时
D.
当鼠标箭头旁边出现一个问号时
【单选题】选择滚动轴承配合时,当负荷方向不变时,转动套圈应比固定套圈的配合()。
A.
B.
C.
相同
D.
松紧
相关题目: