Inasampleofdouble -stranded DNA, 30%ofthe nitrogenous basesarethymine (T). WhatpercentageofthebasesareGuanine(G)?
A. 20%
B. 30%
C. 40%
D. 60%
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HowdidtheAvery-MacLeod-McCartyexperimentexpandonFrederickGriffith'sobservations?
A. ItsuggestedthatDNAisthe“transformingprinciple."
B. ItconfirmedthatDNAisadoublehelixcomposedoftwoantiparallelstrands.
C. ItdemonstratedthatDNAconsistsoffournucleotideswheretheproportionsofadenine/thymineandcytosine/guanineremainconstant.
D. ItprovedthatDNAissemiconservativelyreplicated.
Whichofthefollowingstatementsistrueregardingthediscoveryofthedoublehelix?
A. RosalindFranklin’sx-raycrystallographyprovidedWatsonandCrickwithimportantdatathathelpeddeterminethestructureofDNA.
B. JamesWatson,FrancisCrick,MauriceWilkins,andRosalindFranklinwereawardedtheNobelPrizeinMedicinefortheirdiscoveryofthedoublehelix.
C. TheexperimentsthatledtothediscoveryofthedoublehelixultimatelydisprovedChargaff'srulesregardingnitrogenousbases.
D. Itwasdiscoveredthatdouble-strandedDNAisaparallelmolecule.
WhichofthefollowingstatementsistrueregardingDNAstructure?
A. DNAiscomposedofaminoacids
B. InDNA,purinespairtogetherandpyrimidinespairtogether
C. DNAformsadoublehelix
DNAissingle-stranded
Which of the following statements about DNA structure is FALSE?
A nucleotide consists of a deoxyribose, a phosphate, and a nitrogenous base.
B. Purines consist of two fused rings; pyrimidines have one ring.
C. The “backbone” of DNA consists of alternating sugar and base components.
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