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
The deathwatch beetle is thought of as the devil’s pest in churches and old houses, but in natural habitats it infests a wide ra
The deathwatch beetle is thought of as the devil’s pest in churches and old houses, but in natural habitats it infests a wide ra
admin
2011-01-05
24
问题
The deathwatch beetle is thought of as the devil’s pest in churches and old houses, but in natural habitats it infests a wide range of decaying hardwoods. It has been found in hornbeam, sweet chestnut, hawthorn, beech, ash, blackpoplar, elm, larch, spruce and yew, but the two most commonly infested species in Britain are oak and willow. In buildings, oak timbers are usually the focus of attack by the beetle, but alder, walnut, elm, larch and Scots pine can be affected too. Deathwatch beetles attack wood that has been decayed by fungi, so it is the damp-prone parts of timbers, at the ends and near leaking gutters and enclosed spaces that are normally attacked first.
Adult beetles emerge from holes in the timber in spring, or occasionally in autumn. They breed once and a week or two later the females lay eggs, usually about fifty, in small cracks on the surface of the wood. Adults depend on stored reserves; they do not feed, so the adult lifespan is largely determined by body size and metabolic demands. Emergent females rarely live for more than ten weeks, and males eight or nine weeks, at a temperature of about 20%.
The eggs hatch after two to five weeks and the larvae then wander across the wood to find suitable entry points through which to bore into the timber. Then they take between two and ten weeks to complete their development. The larvae pupate in late summer to early autumn, each individual having constructed a pupal cell just below the surface of the wood. After two or three weeks, the immature beetle emerges from the pupal skin, but then remains torpid inside the chamber until the following spring or early summer. The mature beetle then cuts a perfectly round hole, three to five millimetres in diameter, and emerges covered in a fine layer of wood powder.
SUMMARY :
The deathwatch beetle is found most often in【66】trees in Britain. They infest damp-prone timber which has been affected【67】. Adults do not feed, so they survive on【68】and live for only two or three months. The larvae, on the other hand, live for up to【69】. They pupate in late summer to autumn, but the adult does not emerge until【70】or early summer.
选项
答案
ten weeks
解析
(根据最后一段第二句可知,幼虫需要2至10周的时间来发育。)
转载请注明原文地址:https://jikaoti.com/ti/pStMFFFM
本试题收录于:
B类竞赛(英语专业本科专科)题库大学生英语竞赛(NECCS)分类
0
B类竞赛(英语专业本科专科)
大学生英语竞赛(NECCS)
相关试题推荐
SummaryListentothepassage.Forquestions26~30,completethenotesusingnomorethanthreewordsforeachblank.Rud
Therecessionhasbroughtaboutanabruptchangeofmoodonuniversitycampusesupanddownthecountry.Afive-yearboominthe
Thesedays,collegelecturehallsintheUnitedStatesarebeingfilledmoreandmorewithfemaleratherthanmalestudents.Wom
Thesedays,collegelecturehallsintheUnitedStatesarebeingfilledmoreandmorewithfemaleratherthanmalestudents.Wom
Thesedays,collegelecturehallsintheUnitedStatesarebeingfilledmoreandmorewithfemaleratherthanmalestudents.Wom
SummaryListentothepassage.Forquestions26-30,completethenotesusingnomorethanthreewordsforeachblank.Ele
SummaryListentothepassage.Forquestions26-30,completethenotesusingnomorethanthreewordsforeachblank.Ele
Theideaofhavingasinglecareerisbecominganold-fashionedone.Thenewfashionwillbetohaveseveralcareersorwaysof
Ifthereisanysingle【21】thatmakesforsuccessinliving,itistheabilitytoprofitbydefeat.EverysuccessIknowhasbeen
Ifthereisanysingle【21】thatmakesforsuccessinliving,itistheabilitytoprofitbydefeat.EverysuccessIknowhasbeen
随机试题
公务员的退休程序。
统一化
随楔状缺损加深可出现的并发症除外
桥梁承载能力检测评定,大吨位车辆混入率指车辆质量超过()的车辆所占比例。
有关民用建筑空调系统自动控制的目的,叙述不正确的是()
道路班车客运与其它客运服务营运方式的区别主要体现在()。
根据证券法律制度的规定,下列有关证券投资基金发行和交易的表述中,正确的是()。
德育过程是对学生知、情、意、行的培养提高过程,其实施顺序是()。
2003年一季度.京津沪渝穗五市分别实现房地产投资118.0亿元、30.5亿元、139.8亿元、43.7亿元和70.7亿元,同比增长20.2%、50.1%、29.6%、41.3%和8.8%。五市房地产投资占总投资比重分别为54.0%、24.4%、38.3%
Inagrarian(农业的),pre-industrialEurope,"you’dwanttowakeupearly,startworkingwiththesunrise,haveabreaktohavethe
最新回复
(
0
)