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
专升本
It takes a long time to grow a tree. How long? Well, pine trees are the quickest growing trees, but still, they take twenty year
It takes a long time to grow a tree. How long? Well, pine trees are the quickest growing trees, but still, they take twenty year
admin
2013-12-10
12
问题
It takes a long time to grow a tree. How long? Well, pine trees are the quickest growing trees, but still, they take twenty years to reach a size suitable for cutting and harvesting. An oak takes about sixty years to grow to a good size. A redwood may take hundreds of years.
Lumber companies, which make their money on trees, depend on those that grow quickly.
Therefore
, they are always looking for methods to make trees grow faster. So far, the secret to fast growing trees seems to lie in " super-seeds. " These are seeds that are gathered from the quickest growing trees in a forest. One company searched 100,000 acres of trees and selected the seeds from just fifteen trees. These two ounces of seed were enough to plant several hundred new trees. Eventually, when these trees have grown, seeds will again be taken only from the fastest growing trees of crop. This process of artificial selection will yield, in the future, a super-tree that will grow in half the time it takes normal trees to develop.
Unfortunately, it takes a long time for a plan like this to reach its goal. The Weyerhauser Lumber Corporation, which started its first collection of seed in 1958, is just now beginning to harvest the super-seeds of the first generation of the faster growing trees.
This selection centers on______.
选项
A、the life span of trees
B、the age of redwoods
C、making trees grow quickly
D、cutting trees for lumber
答案
C
解析
全文讲了如何才能使树木成长得快一点。Life span寿命。选项C是正确的。
转载请注明原文地址:https://kaotiyun.com/show/YOeC777K
本试题收录于:
英语题库成考专升本分类
0
英语
成考专升本
相关试题推荐
Atonetimeoranotherwehaveallstoppedtothinkabouttheweather.Somedaystheweatherisgood.Somedaystheweatherisb
Television—thatmostattractivemoderntechnology,markedbyrapidchangeandgrowth—ismovingintoanewerawhichpromisesto
SequoyahwasayoungCherokeeIndian,sonofawhitetraderandanIndianSquaw(北美印第安女人).Atanearlyage,hebecamefascinated
Asprotectorofherfamily’shealth,thepoineerwomanconfrontedsituationssheneverimaginedbeforecrossingtheMississippi.
Tousitseemssonaturaltoputupanumbrellatokeepthewateroffwhenitrains.Butactuallytheumbrellawasnotinvented
Muchsocialtalk,【36】fromcasualconversationtoformal【37】speechhasanaimotherthantoconveyinformationortoachieveagre
AcrosstheUnitedStates,scientistsaremountingwhatmaybecomethemostinnovativeagriculturalresearchdrivesincethe1920
ArchimedeswasafamousGreekmathematicianandscientist.Hewasbornaround287BCandhediedintheyear212BC.Archime
ArchimedeswasafamousGreekmathematicianandscientist.Hewasbornaround287BCandhediedintheyear212BC.Archime
ThereoncelivedapoortailorwhohadasoncalledAladdin,acareless,idleboy【21】woulddonothingbutplayalldaylongint
随机试题
根据《行政处罚法》规定,违法行为在二年内未被发现的,不再给予行政处罚。法律另有规定的除外()
6有机化工产品的特性与它的()有密切关系。
腊肠犬,雌性,8岁,不愿挪步,行动困难,不愿让主人抱。精神欠佳,食欲下降,腹围增大,尿失禁,肛门反射迟钝,触诊腰部皮肤紧张、痛叫。根治该病最有效的方法是
职业道德评价的作用有()。
建筑屋面各汇水范围内,雨水排水立管不宜少于()根。
公司希望通过历史数据和资料来预测下一年的市场销量,比较适合采用()。
公安机关在办理刑事案件中,在()应当用当地通用的语言进行讯问。
(单选题)近年来,网咖呈高速发展之态势,让人欢喜让人忧。喜的是网咖出现是我国经济快速发展的产物,是开放社会的一个象征;忧的是一些网咖无序发展,唯利是图,衍生社会公害。网咖发展的“让人欢喜让人忧”表明()。
若α∥β,α={6,3,一2},而|β|=14,求β.
A、Theylosttheirway.B、Theyforgotwhattheyweredoing.C、Theyweresleepy.D、Theyhadmentalmistakes.B该题问“根据本段,为什么人们在疲倦时易于
最新回复
(
0
)