Question

After cells take up one form of this molecule, it becomes accessible for antibody labeling after its target is hydrolyzed with HCl (“h-c-l”) and borax. That form of this molecule is often co-stained with Ki67 (“k-i-67”). This non-methylated molecule is the larger product of a reaction catalyzed by APOBECs, which underpins the first step of bisulfite sequencing. Ethynyl- and bromo·de·oxy derivatives of this molecule are used to detect cell proliferation. The letter (*) psi denotes a form of this molecule that may help strengthen binding to the 30S subunit in one structure’s stem-loops. This molecule (-5[1])is generated by de·aminating cytosine, and methylating this molecule’s 5’ (“five-prime”) carbon yields its more mutation-resistant analog that similarly forms two hydrogen bonds with adenine. For 10 points, (-5[1])what base replaces thymine in RNA? (10[1])■END■ (10[1])

ANSWER: uracil [or U; or uridine; accept bromodeoxyuridine or BrdU; accept ethynyl deoxyuridine or EdU; accept pseudouridine; prompt on thymine or thymidine until “APOBECs” is read by asking “thymine/thymidine is a derivative of what other molecule?”]
<JE, Biology>
= Average correct buzz position

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Buzzes

PlayerTeamOpponentBuzz PositionValue
Shahar SchwartzBerkeley PastBerkeley B91-5
Swapnil GargBerkeley AStanford118-5
Michal GerasimiukStanfordBerkeley A12410
Hansen JinBerkeley BBerkeley Past12510

Summary