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