oducedbyafluteorwhistle.Thehighsoundsareproducedwhentheairispreventedbytheholesfromgoingthrough,whilethelowsoundsareproducedbyallowingmoreoftheairtopass.Allthisiswhatproducesthedifferencesbetweenhighandlowsounds.Theloudnessofasoundisevidentlyproducedbyhowmuchthemembraneiscausetomove.Whetherornothearingisreallyproducedinallanimalsbytheeffectofpressureisnotdefinitelyknownbyscientistsasyet.Wedoknow,however,thatnaturehassetupsomeverydelicatehearingmechanismsforitscreatures.Scientistsmustexploremuchfurtherformoreknowledgeabouthowanimalsusetheirears.41.AccordingtothearticlepracticallyallanimalshavesomesenseofA.directionB.hearingC.vibrationD.bothBandC42.ThecochleaisfoundA.infishB.onlyinhumansC.inallanimalsD.inallmammals43.ScientistsknowA.thatallanimalshaveacochleaB.verylittleabouthearinginanimals
全文预览
