简述生地黄、玄参、牡丹皮、赤芍的药性特点、功效、应用。并比较前两者、后两者的功效、应用的异同点。
Which of the following is true for the process of RNA synthesis?
A. Occurs in the 3′ to 5′ direction
B. Requires primer
C. Does not require primer
D. Is initiated at special DNA sequences known as start condons
Eukaryotic promoters contain:
A. TATA box 25 bp upstream of transcription start site
B. CAAT box 70 to 80 bp upstream of transcription start site
C. Both (a) and (b)
D. None of these
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