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
Pheromones are substances that serve as chemical signals between members of the same species. They are secreted to t
Pheromones are substances that serve as chemical signals between members of the same species. They are secreted to t
admin
2004-12-28
89
问题
Pheromones are substances that serve as chemical signals between members of the
same species. They are secreted to the outside of the body and cause other individuals
of the species to have specific reactions. Pheromones, which are sometimes called
line "social hormones," affect a group of individuals somewhat like hormones do an individual
(5) animal. Pheromones are the predominant medium of communication among insects
(but rarely the sole method). Some species have simple pheromone systems and produce
only a few pheromones, but others produce many with various functions. Pheromone
systems are the most complex in some of the so-called social insects, insects that live
in organized groups.
(10) Chemical communication differs from that by sight or sound in several ways.
Transmission is relatively slow (the chemical signals are usually airborne), but the
signal can be persistent, depending upon the volatility of the chemical, and is sometimes
effective over a very long range. Localization of the signal is generally poorer than
localization of a sound or visual stimulus and is usually effected by the animal’s moving
(15) upwind in response to the stimulus. The ability to modulate a chemical signal is limited,
compared with communication by visual or acoustic means, but some pheromones may
convey different meanings and consequently result in different behavioral or physiological
responses, depending on their concentration or when presented in combination. The
modulation of chemical signals occurs via the elaboration of the number of exocrine
(20) glands that produce pheromones. Some species, such as ants, seem to be very articulate
creatures, but their medium of communication is difficult for humans to study and
appreciate because of our own olfactory, insensitivity and the technological difficulties
in detecting and analyzing these pheromones.
Pheromones play numerous roles in the activities of insects, They may act as alarm
(25) substances, play a role in individual and group recognition, serve as attractants between
sexes, mediate the formation of aggregations, identify foraging trails, and be involved in
caste determination. For example, pheromones involved in caste determination include
the "queen substance" produced by queen honey bees. Aphids, which are particularly
vulnerable to predators because of their gregarious habits and sedentary nature, secrete
an alarm pheromone when attacked that causes nearby aphids to respond by moving away.
选项
A、How insects use pheromones to communicate
B、How pheromones are produced by insects
C、Why analyzing insect pheromones is difficult
D、The different uses of pheromones among various insect species
答案
D
解析
转载请注明原文地址:https://kaotiyun.com/show/jZ8O777K
0
托福(TOEFL)
相关试题推荐
ReadthetextbelowandanswerQuestions7-14.INTERCITYSleeperbetweenLondonandScotlandMostticketsmayb
DothefollowingstatementsagreewiththeclaimsofthewriterinReadingPassage3?Inboxes32-37onyouranswersheet,write
Youshouldspendabout20minutesonQuestions1-14.CREATIVETOYSABathtimeanimalsFivefoammix-and
ChoosethecorrectletterA,B,CorD.Writeyouranswersinboxes6-9onyouranswersheet.Whydoestheauthormentionthep
Youshouldspendabout20minutesonQuestions14-26whicharebasedonReadingPassage2below.ITWASthesummer,scientistsn
Thestartoftheautomobile’shistorywentallthewaybackto1769whenautomobilesrunningonthesteamenginewereinventeda
HowdidthetravellerhearaboutNewYork?WhatsurprisedthetravelleraboutNewYork’sairport?
Completethenotesbelow.WriteNOMORETHANTWOWORDSforeachanswer.HowtokillbadinsectsChemicalmethodsThesesolutions
Completethesentencesbelow.WriteNOMORETHANTWOWORDSforeachanswer.Harmfulinsectsmaydestroycrops,clothes,furnitu
A、Thepopulationsofsmalltownsincreasedrapidly.B、Artcriticsincitesbegantotakenoticeofregionalism.C、Someregionali
随机试题
下列哪位作家主张“文必秦汉,诗必盛唐”()
首次从理论上论证班级授课制的教育家是()
对被检者防护无关的是
李某于2007年7月在一物业管理比较完善的小区内购得一套普通住宅,李某还有其他家庭住房,就将本套住宅出租给张某居住。2015年7月后,李某又将该套住宅高于购买价转售出去。对于材料齐全并且符合法定形式,可以出租的房屋,直辖市、市、县人民政府建设(房地产)
与邀请招标相比,公开招标的特点是()。
自主支付方式下由于贷款人在放款前会像贷款人受托支付方式下详细审查贷款资金用途,因此贷款人不必过度加强对贷款资金用途的后续跟踪核查。()
杜能圈的第三圈是()。
影响知识识记与编码的主要因素有哪些?
根据我国有关法律规定,全国人民代表大会预备会议的主要内容有()(2010年非法学综合课多选第56题)
BenjaminFranklinisportrayedinAmericanhistoryasthequintessentialself-mademan.In“Self-reliance,”Emersonasks,“Where
最新回复
(
0
)