1. Sex lethal (SXL) in Drosophila is transcribed when

A. the X autosome balance is less than 0.5
B. the X autosome balance is 1 or greater
C. the X autosome balance equals 0.5
D. none of the above

2. A mutation in the tip binding site of the repressor would result in

A. constitutive trp operon expression
B. inducible trp operon expression
C. no operon expression
D. none of the above

3. The first protein complex to bind to the TATA box is

A. transcription factor IIA
B. transcription factor IIB
C. transcription factor IID
D. all of these

4. Which of the following is not part of the lac operon?

A. I
B. O
C. P
D. none of these

5. The lac operon is transcribed in which segments?

A. 1
B. 2
C. 3
D. 4