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
Bees that help with pollination benefit flowers and【L31】________. Bees produce wax that can be made into candles and【L32】_______
Bees that help with pollination benefit flowers and【L31】________. Bees produce wax that can be made into candles and【L32】_______
admin
2022-09-09
18
问题
Bees that help with pollination benefit flowers and【L31】________.
Bees produce wax that can be made into candles and【L32】________.
Dragonflies primarily eat【L33】________.
Insects in summer can be harmful because they can carry such deadly diseases as malaria,
yellow fever, and【L34】________.
Harmful insects may destroy crops, clothes, furniture, and even the【L35】________.
【L31】
Good afternoon, and welcome to Insect Biology 101. I’d like to begin this course with a few remarks about good insects and bad ones. Bugs are all around us and that’s both a benefit and an annoyance — sometimes maybe even serious harm. First, let’s talk about the good things that insects do for us.
Probably the most important insect for humans, and maybe for all other life, is the bee. Bees help plants in the process of pollination, and
thus are necessary to most flowers and fruit trees
. That is, they carry pollen from ‘male’ flowers to ‘female’. If it weren’t for bees, we’d have very few food plants and no fruit either. In fact, there would be no ‘we’. No less a thinker than Albert Einstein pointed out that, without bees, humanity would be dead within a year or less. We’d starve. It’s that simple. That should maybe make us just a little humble.
A little less dramatic is the fact that bees also make the honey we eat. Moreover,
they produce beeswax, which is useful in candles and it’s also used as a first-rate furniture polish
. Sure, these may not be vital to our lives, but they can serve as reminders of how important bees are. That’s a point I keep coming back to in this course. Though, in all fairness, I should point out that butterflies aid in pollination as well as bees.
Now, here in Michigan, what’s the worst part of summer? Yep, that’s right — mosquitoes. But I’m talking about helpful insects, right? So let’s look at the dragonfly first. If there were no dragonflies, there would be even more mosquitoes!
Dragonflies mainly eat mosquitoes and also a few other insects
. Yes, that’s right. They don’t just fly around, and they also help to eliminate harmful insects. So, the next time you see a dragonfly, don’t you dare kill it!
Now let’s talk a little about those harmful insects. Take the mosquitoes I just mentioned as an example. Not so many years ago, mosquitoes here in America weren’t just annoying. Some were even deadly. They carried malaria and yellow fever. My own ancestor, the Confederate General John Bell Hood, lived through the worst battles of Civil War only to die at age thirty-eight from yellow fever. A pest, not a bullet!
Well, besides the mosquitoes, in summer there is also a kind of insect that never seems tired. Right, that is the fly. Before I go on talking, I must mention an African fly called the Tsetse fly, which feeds on blood and can cause serious diseases in the people and animals that it bites.
Besides, it is still a bearer of sleeping sickness
, which affects around 300,000 people every year in Africa and can be treated only with toxic drugs that are hard to administer. Worse still, the drugs sometimes don’t work.
Other insects, of course, destroy food crops. In China, for instance, locusts continue to be a danger to the harvest in some areas. Less important, but still annoying, moths eat people’s clothes and dust mites slowly destroy carpets. Worse, but still in the home, termites or "white ants" eat wood — the wood of your house.
If they are not stopped, they can eventually destroy the whole building
. Usually, they seriously damage a building before anyone even notices them. So, as we all know, insects can be a real trouble.
For some decades in the West, to kill insects with chemicals seemed a good remedy. Unfortunately,
chemicals can only be used in a limited area for a limited time. It’s a small-scale solution
. The insects come back. Worse still, some of the poisons used like DDT were found harmful to the environment. Many kinds of wildlife, like hawks, were harmed. And people in chemical-using rural areas have one of the highest rates of liver cancer in the world.
It’s no secret that the chemicals remain harmful to humans
.
Like all species, insects adapt to their changing environments at an amazing rate. When a new chemical is introduced to their habitat, the insects that survive are generally the ones with some way of resisting the harmful effects. They then breed with the other survivors, and
just like that insects become resistant to most poison in a few generations
. An insect generation, remember, is a couple of months at most!
So, again we have to ask: what to do? Well, there are biological solutions. Some of these are pretty simple. One is destroying the insects’ habitat. You take away their home or food. Cleaning your kitchen is the best way to prevent roaches. No garbage: no food. Getting rid of marshes and swamps eliminates mosquitoes. Other solutions might include bringing in dragonflies or bats in areas where mosquitoes are many.
This is a cheaper alternative to chemicals
. Biological methods like this also bring no extra pollution to the environment. But you have to be careful. If you change the environment too much, you might be hurting other forms of life accidentally.
One recent method of controlling insect populations involves interrupting their breeding cycle. What does that mean? It means ‘birth control for bugs’. Insects are provided with food that makes them unable to reproduce. Since they can’t have babies, the population disappears, or nearly so. And since no young are born, resistance is not a problem with no young insects developing increased resistance.
Interrupt the life cycle, eliminate the bug!
It’s clear that we must have an understanding of the life cycle of the insect
. At least, that’s the plan. We’ll go into more details as this course goes along. Now I will stop here to see whether you have any questions or not.
选项
答案
fruit trees
解析
空格前为and,推测应填入和flowers并列的名词。录音原文中的help…pollination是的原词复现,录音中的are necessary to是benefit的替换表达,故空格处应填入fruit Wees。
转载请注明原文地址:https://jikaoti.com/ti/h6biFFFM
本试题收录于:
雅思听力题库雅思(IELTS)分类
0
雅思听力
雅思(IELTS)
相关试题推荐
)有以下程序:#include<stdio.h>main(){FILE*fp:inta[10]={1,2,3,0,0},i:fp=fopen("d2.dat","wb"):fwrite(a,sizeof(int),5,fp);fwrite(
中国注册税务师协会宣传处王干事正在准备一份介绍本协会的演示文稿,按照下列要求帮助王干事组织材料完成演示文稿的整合制作,完成后的演示文稿共包含15张幻灯片,且没有空白幻灯片。1.在考生文件夹下,打开空白演示文稿“PPT.pptx”,根据Word文档
将考试文件夹中的声音文件“BackMusic.mid”作为该演示文稿的背景音乐,并要求在幻灯片放映时即开始播放,至演示结束后停止。
PeopleallovertheworldknowWimbledonasthecentreoflawntennis.In1874itwasacountryvillage,butitwasthehome
Makinggoodchoicesaboutyourownhealthrequiresreasonableevaluation.Akeyfirststepinbetteringyourevaluationability
EachtimeItaketheunderground1findmyself【K1】________(surround)bydozensofpassengersplayingsmart-phones.Theyalmostw
Accordingtothespeaker,howlonghasKettyPerryworkedasaconsultant?
cupboard该题询问的是第二个书柜的其他特征(otherfeatures)。录音中的atthebottom是题干的原词复现,故这里填入cupboard。表示这个书柜的底部有一个橱柜可以用来放一些零散的东西。
TheGherkinBuildingCommissionedby:【L31】________firmcalledFosterandPartnersThefeaturesofitsappearance:Itsshapeis
InShakeShackCompany,astherestaurantmanager,youwillberesponsibleforhelpingtoleadanddrivethedailyoperationsof
随机试题
苏州最大的佛塔是(),素有“江南第一古塔”之誉。
自然界与人类社会的分化和统一的基础是()
下列关于唇癌的描述中,不正确的是
A.长脉B.短脉C.缓脉D.迟脉E.数脉
我国进出口药品管理实行分类和目录管理,即将药品分为进口麻醉药品、进出口精神药品以及进口一般药品。国家药品监督管理局会同国务院对外贸易主管部门对上述药品依法制定并调整管理目录,以签发许可证件的形式对其进出口加以管制。甲药品经营企业采用虚假材料骗取批准证明
下列哪些组织不可以自己的名义提起行政诉讼?()
根据美国的个人所得税制度的规定,当()出现时,夫妇俩才可以进行联合申报。
中央俱乐部
有如下程序:#inc1ude<iostream>usingnamespacestd;classVAC{public;intf()const{return3;}intf(){retu
Internet提供的服务有很多,( )表示网页浏览。
最新回复
(
0
)