Unformatted text preview: b. When a partial diploid is formed with an F1 plasmid carrying a wild-type lac operon, synthesis becomes inducible. What was the genotype of the mutant? 5. Certain mutants of the lacI repressor gene do not bind lactose but do bind to the operator. In these strains, do you think β-galactosidase synthesis is inducible or constitutive, or neither? 6. Certain bacteria are known that metabolize crude oil. How would you test whether the enzymes that break down the oil are constitutive or inducible? 7. How does bacteriophage lambda decide whether to grow lytically or to lysogenize a newly infect host? What are the roles of the cI, N, and cro proteins in these decisions? What about cll? 8. What are the properties expected of mutants in cI, N, cro, and cII with respect to the propensity for lytic growth or lysogeny? Why? 9. Why do cIII mutants fail to lysogenize?...
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- Fall '08
- Genetics, lac repressor, ype lac operon, operon inducer co-repress, protein trp operon