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
Where Have All the Bees Gone? Scientists who study insects have a real mystery on their hands. All across the country, honey
Where Have All the Bees Gone? Scientists who study insects have a real mystery on their hands. All across the country, honey
admin
2013-10-25
48
问题
Where Have All the Bees Gone?
Scientists who study insects have a real mystery on their hands. All across the country, honeybees are leaving their hives and never returning. Researchers call this phenomenon colony-collapse disorder. According to surveys of bee keepers across the country, 25 to 40 percent of the honeybees in the United States have vanished from their hives since last fall. So far, no one can explain why.
Colony collapse is a serious concern because bees play an important role in the production of about one-third of the foods we eat. As they feed, honeybees spread pollen from flower to flower. Without this process, a plant can’t produce seeds or fruits.
Now, a group of scientists and beekeepers have teamed up to try to figure out what’s causing the alarming collapse of so many colonies. By sharing their expertise in honeybee behavior, health, and nutrition, team members hope to find out what’s contributing to the decline and to prevent bee disappearance in the future.
It could be that disease is causing the disappearance of the bees. To explore that possibility, Jay Evans, a researcher at the United States Department of Agriculture(USDA)Bee Research Laboratory, examines bees taken from colonies that are collapsing. "We know what a healthy bee should look like on the inside, and we can look for physical signs of disease, " he says. And bees from collapsing colonies don’t look very healthy. "Their stomachs are worn down, compared to the stomachs of healthy bees, " Evans says. It may be that a parasite is damaging the bees digestive organs. Their immune systems may not be working as they should. Moreover, they have high levels of bacteria inside their bodies.
Another cause of colony-collapse disorder may be certain chemicals that farmers apply to kill unwanted insects on crops, says Jerry Hayes, chief bee inspector for the Florida Department of Agriculture. Some studies, he says, suggest that a certain type of insecticide affects the honeybee’s nervous system(which includes the brain)and memory. "It seems like honeybees are going out and getting confused about where to go and what to do, " he says.
If it turns out that a disease is contributing to colony collapse, bees genes could explain why some colonies have collapsed and others have not. In any group of bees there are many different kinds of genes. The more different genes a group has, the higher the group’s genetic diversity. So far scientists haven’t determined the role of genetic diversity in colony collapse, but it’s a promising theory, says Evans.
According to the fifth paragraph, which of the following about bees’ genes is true?
选项
A、Bees’ genes allow them to expand their colonies.
B、Bees’genes help keep them in their hives.
C、Bees’genes make them fly from flower to flower.
D、Bees’genes could explain the collapse of some colonies.
答案
D
解析
转载请注明原文地址:https://kaotiyun.com/show/rXmd777K
本试题收录于:
职称英语卫生类B级题库职称英语分类
0
职称英语卫生类B级
职称英语
相关试题推荐
CONVERSATION2(Questions5-8)Fred’sjob:【L5】______driver.Yearsfordoingthejob:【L6】______.ProblemsFredhad:troublewith
Lookatthetenstatementsforthispart.Youwillhearastoryabout"CommunicationThroughTime".Decidewhetheryou
CONVERSATION2(Questions5-8)Fred’sjob:【L5】______driver.Yearsfordoingthejob:【L6】______.ProblemsFredhad:troublewith
CONVERSATION2(Questions5-8)Fred’sjob:【L5】______driver.Yearsfordoingthejob:【L6】______.ProblemsFredhad:troublewith
DEALINGWITHWASTEPLASTICEveryyearpeoplethrowawaymillionsoftonnesofplasticbottles,boxesandwrapping.Thesecr
Whatisthewritertryingtodeinthetext?CustomerschooseMrBirdbecausehisshoes
HealthInsurance(保险)MostAmericansareresponsiblefortheirownmedicalcosts.Thesecanbeextremelyhighifapersonge
BathingintheseainEnglandahundredyearsagowasnotquitethelight-heartedamusementthatitistoday.Therearenorunni
HisnoveldepictsanambitiousAmerican.
Babies’ResponseForsometimeinthepastithasbeenwidelyacceptedthatbabies,andothercreatureslearntodothingsb
随机试题
关于中国各民主党派形成时的社会基础的说法,不正确的是()
下列不是恶性肿瘤的是
“C”形根管多见于
按检定性质,项目部的计量器具分为A、B、C三类,属于B类的计量器具是()等。
在施工项目形成过程中,对施工项目成本进行对比评价和总结的工作是成本()。
在现金流量表附注中将净利润调整为经营活动的现金流量时,需要调整的项目有()。
当英特尔公司开发出一种电脑芯片时,如果该芯片明显优于竞争芯片,那么英特尔就会设定它能够设定的最高价格。当销售量下降时,或者当受到竞争对手开发出类似芯片的威胁时,英特尔就会降低芯片价格,以便吸引对价格敏感的新顾客层。如果英特尔公司降低了芯片价格,则可以推出(
将国际市场划分为工业化国家市场、中等收入国家市场、低收入国家市场,这种划分是()。
为什么说在一个特定期间内资产的现金流量为负不一定不好?
--Weretheylatefortheplay?--Notreally.Assoonasthey______themselvesintheirseatsinthetheatre,thecurtain
最新回复
(
0
)