11. Which of the following enzyme(s) is/are required for lactose fermentation?
A. Transacetylase
B. β-galactosidase
C. Galactoside permease
D. All of these
12. Which of these catalyzes the synthesis of RNA from a DNA template?
A. DNA gyrase
B. DNA ligase
C. DNA polymerase
D. RNA polymerase
13. A level of regulation, demonstrated by the termination of transcription if tryptophan is abundant, by the tryptophan operon in E.coli cells is called
A. activation
B. attenuation
C. corepression
D. desiccation
14. An mRNA transcript of a gene contains
A. a start codon
B. a stop codon
C. a terminator
D. all of these
15. Which of the following proteins first binds to TATA box during transcription?
A. TF II A
B. TF II D
C. TF II B
D. RNA polymerase