下面小编跟大家一起了解托福听力单项突破练习分享，希望对大家的学习有所帮助。

1.Whatisthelecturemainlyabout?

A.EvidenceprovingthatwaterwasonceonMars

B.ScientificanalysescurrentlybeingdoneonmineralsamplesfromMars

C.RecentdevelopmentsthatcouldhelpdeterminewhetherlifeeverexistedonMars

D.AnapproachtodeterminingwhetheraminoacidsonEarthoriginatedonMars

2.WhatwasdiscoveredonMarsthatsuggestswateronceexistedthere?

A.Microorganismsthatcanformonlyinthepresenceofwater.

B.Amineralthatcanformonlyinthepresenceofwater.

C.ProteinsthathavethesamestructureasproteinsfoundonEarth.

D.Largedepositsofironandpotassiumthatcanformonlyinthepresenceofwater.

3.HowmightjarositefoundonMarsdifferfromjarositefoundonEarth?

A.MarsjarositeandEarthjarositemighthavebeencreatedbydifferentprocesses.

B.Marsjarositemighthavebeenformedwithoutwater.

C.MarsjarositemightnotcontainasmuchironorpotassiumasEarthjarosite.

D.MarsjarositemightbemoreacidicthanEarthjarosite.

4.Accordingtotheprofessor,whataretwoimportantcapabilitiesofthemicrofabricatedorganicanalyzer?Clickon2answers

A.Itcanaccuratelytestforthepresenceofwater.

B.ItcananalyzesoilsampleswithoutreturningthemtoEarth.

C.ItcanreturnsoilsamplesbacktoEarthquickly.

D.Itcandeterminethehandednessofaminoacids.

5.WhatpointdoestheprofessormakeaboutthetwentyaminoacidsthatoccuronproteinsonEarth?

A.Theycanbeeitherright-handedorleft-handed.

B.Theyweresynthesizedthroughabioticprocesses.

C.Theyallhaveacrystallinestructure.

D.Theyareallleft-handed.

6.Whatwouldaprevalenceofright-handedaminoacidsinmineralsamplescollectedonMarsindicate?

A.ThataminoacidsonMarsprobablyoriginatedonEarth

B.ThataminoacidsexistedonMarslongbeforetheyexistedonEarth

C.ThatatypeofmicroorganismmayhaveexistedonMarsthatisdifferentfromanyonEarth

D.Thatleft-handedaminoacidsareprobablypresentinsomemineralsonMars