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
A、Collect ash tree seeds for experiment. B、Preserve the healthy ash tree seeds. C、Set up a new seed bank for research. D、Develop
A、Collect ash tree seeds for experiment. B、Preserve the healthy ash tree seeds. C、Set up a new seed bank for research. D、Develop
admin
2013-06-02
46
问题
A beetle invasion in the United States has killed at least twenty million ash trees. The invasion of the emerald ash borer was first discovered near Detroit, Michigan, in 2002. Experts believe the small green insects arrived in the 1990’s in shipments of goods from China.
The emerald ash borer has destroyed trees in the Midwest and as Far East in the United States as Maryland. The insects have also spread as far north as Ontario, Canada.
Ash trees can resist many diseases. But they cannot resist the emerald ash borer. It lays eggs on the bark. The young larva drill into and feed on the inner bark. This harms the ability of the tree to transport water and nutrition.
In some places, farmers .are using "detection trees". They have an area where bark has been cut away. The area circles the tree. The process weakens the tree. It makes them easier targets for borers, and shows if the insects are nearby.
Efforts to stop the spread of the emerald ash borer include cutting down affected trees. There are worries that the ash tree might disappear unless the invasion is controlled. To prepare for such a possibility, a government laboratory is asking people to send in the seeds from ash trees. It examines and X-rays the seeds to make sure that there are no living borer fertilized eggs. Only the best seeds are remained and then sent for storage in a seed bank. There, they are dried and frozen. Should the seeds ever be needed, the hope is that scientists might someday develop an ash tree that could resist the little green attackers.
选项
A、Collect ash tree seeds for experiment.
B、Preserve the healthy ash tree seeds.
C、Set up a new seed bank for research.
D、Develop a new breed of ash tree.
答案
B
解析
短文说,实验室对种子进行检查和照X-ray,确保没有钻孔虫的受精卵,只有最好的被保存起来。故答案是B。
转载请注明原文地址:https://kaotiyun.com/show/a8B7777K
0
大学英语六级
相关试题推荐
Theissueofwhetherparentswhosechildrenareobeseshouldbechargedwithneglecthasfueleddebateandgeneratedcontroversi
Hotelseagertosatisfythegrowingdesireofbusinesstravelersforeco-friendlylodgingarefindingthattheirenvironmentala
TheOnlyChild;RevealingtheMythsAccordingtotheGuttmacherInstitute,aleadingreproductive-healthresearchorganizati
Olderpeoplewhoholdtemporaryorpart-timejobsafterretirementenjoybetterphysicalandmentalhealththanthosewhostopw
I’vealwaysbeenanoptimistandIsupposethatisrootedinmybeliefthatthepowerofcreativityandintelligencecanmaketh
A、Theeffectsofnoiseonthequalityoflife.B、Theroleofairtrafficrestrictions.C、Theproductionofquieterengines.D、Th
A、Theyhaveaprivatetutor.B、Theygotoaregularschool.C、Theyattendaspecialschool.D、Theyaretaughtbytheirparents.
A、Thebossisoftenlateforwork.B、Thebosswillprobablydisciplinethewoman.C、Thebossmaydisregardthewoman’slateness.
CaloriesForyearsnow,calorieshavebeenalltherage--peoplearecountingthemandcuttingthem,andyou’dbehard-press
A、Driveinthewindandrain.B、ListentoJohn.C、Gotoanindoortheater.D、Seeafilm.D虽然是windyandrainynight风雨交加的夜晚,只能gob
随机试题
因特网(Internet)实现域名和IP地址转换功能的系统称为________。
A.窦房结P细胞B.窦房结过渡细胞C.房室交界细胞D.浦肯野细胞E.心室肌细胞自律性最高的心肌细胞是
女孩,10岁。因膝、肘关节肿痛,伴低热、乏力诊断为儿童类风湿病。眼科检查有虹膜睫状体炎,该病例属于以下哪种类型
慢性盘状红斑狼疮是
患者,男,50岁,因胆结石合并胆道梗阻拟行手术治疗,患者的妻子、父母、大哥及其25岁的儿子都到了医院,医务人员介绍了手术的重要性及风险,其手术协议签订人应首选
甲公司欠乙公司200万元到期货款无力偿还。乙公司经过调查得知下列情况:(1)丙公司与甲公司之间存在货物买卖合同,甲公司已经付款,而丙公司尚未交货,且交货日期已届至。(2)甲公司与丁公司之间存在大型机器设备买卖合同,丁公司共分5期交付货款,在交清货款之前机器
某斜拉桥进行定期检查。经检查,斜拉桥拉索存在保护套开裂现象,评定标度为2(共4级标度)。同时根据频率法对拉索进行了索力测试。结合上述内容,回答下列问题。根据该桥拉索保护套开裂现象评定,该部件应扣()分。
企业在计算下列固定资产投资决策分析指标时,需要直接利用资金成本信息的是( )。
【情境】东南化工科技集团股份有限公司是外资司高集团在华投资,以合资方式成立于1992年8月的集团企业。经过20多年发展,现在形成了位于H省、Y省、L省的三大生产基地,以及华东、东南、东北、西北四大销售服务覆盖网。司高集团为了适应东南化工的快速发展
Oneofthemostinterestingofallstudiesisthestudyofwordsandwordorigins.Eachlanguageis【1】ofseveralearlierlanguag
最新回复
(
0
)