28. The lac operon (lactose operon) is an operon required for the transport and metabolism of lactose in Escherichia coli.
(A) There are lacZ, lacy and lacA genes in lac operon and they are transcribed independently.
(B) The lac repressor encoded by lacl gene is constitutively expressed.
(C) In the presence of glucose, the catabolite activator protein (CAP) is activated to increase LacZ expression.
(D) Lactose is a disaccharide, which can be cleaved by LacZ into fructose and galactose.
(E) RNA polymerase binds to operator in the absence of lactose.
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統計: 尚無統計資料
統計: 尚無統計資料