1. Is an inducible operon normally off or on?

2. Is an inducible operon normally off or on?
Inducible operons are normally off
They are controlled by an active repressor protein
They can be turned on by the presence of an inducer
An example of an inducible operon is the Lac Operon
In that case, allolactose is the inducer

3. Give an example of a repressible operon

4. Give an example of a repressible operon
The trp operon is a repressible operon
Most repressible operons regulate an anabolic pathway

5. Are repressible operons normally off or on?

6. Are repressible operons normally off or on?
Repressible operons are normally on
The repressor protein is normally inactive
The repressor protein can be made active by the presence of a corepressor
Tryptophan is the corepressor for the trp operon

7. Glucose levels are inversely related to?:
Lactose levels
Tryptophan levels
RNA polymerase levels
cAMP levels

8. Glucose levels are inversely related to?:
cAMP levels

9. cAMP binds to?

10. cAMP binds to?
CAP (catabolic activator protein

11. cAMP-CAP complex binds to?

12. cAMP-CAP complex binds to?
The promoter
Now the promoter can bind RNA polymerase
This is only true for operons controlled by the glucose effect, also known as catabolite repression

13. Who discovered the process of transformation?

14. Who discovered the process of transformation?
Griffith
He worked with two strains of Streptococcus pneumoniae in mice
The smooth encapsulated strain was virulent and killed the mice
The rough nonencapsulated strain was avirulent
Dead smooth bacteria “transformed” live rough strains into virulent smooth strains

15. What is an F+ cell?

16. What is an F+ cell? Contains an F plasmid
Contains the genes to form a pilus on the F plasmid
Can conjugate with an F- cell and transfer a copy of its plasmid

17. What is an Hfr cell?

18. What is an Hfr cell?
Contains an F plasmid that has integrated into the bacterial chromosome
Can undergo conjugation and transfer some of its chromosome to another cell

19. When an Hfr cell conjugates with an F- cell, what happens to the recipient cell?

20. When an Hfr cell conjugates with an F- cell, what happens to the recipient cell?