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44. How does extracellular glucose inhibit transcription of the lac operon?
(A) by strengthening the binding of the repressor to the operator
(B) by weakening the binding of the repressor to the operator
(C) by degrading the lac operon gene
(D) by inhibiting RNA polymerase from opening the strands of DNA to initiate transcription
(E) by reducing the levels of intracellular cAMP


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難度: 簡單
1F
Peipool 高三下 (2021/03/18)
乳糖操縱組的成員
CAP site
(1) CAP(catabolite activator protein),又稱作CRP(cAMP rceceptor protein),是一種能與cAMP結合的蛋白,結合後的複合體與CAP site結合後,可促進RNAP轉錄作用。
CAP:為positive regulator,與cAMP形成複體結合至CAP site則操縱組開啟。

當有乳糖時,CAP與cAMP形成複體結合至CAP site則操縱組開啟,導致cAMP水平下降

44. How does extracellular glucose inhib..-阿摩線上測驗