一条直线的水平投影反映其实长，则该直线为一定为水平线。
查看答案
两直线的三面投影都相交时，则空间两直线就一定相交。（）
A. 对
B. 错
空间两直线若不平行，则必定相交。（）
A. 对
B. 错
The specific DNA sequences to which the transcription factors bind are referred to as _____
A.replication elements
B.blocking factors
C.transcription factors
D.regulatory elements
The TATA box is often used as an indicator of the presence of a promoter.
A.True
B.False
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