Shortly after the discovery of kinetin, it was observed that the differentiation of cultured callus tissue derived from tobacco pith segments into either roots or shoots depends on the ratio of auxin to cytokinin in the culture medium. Whereas

a) high auxin:cytokinin ratios stimulated the formation of roots

b) high auxin:cytokinin ratios stimulated the formation of shoots

c) low auxin:cytokinin ratios led to the formation of shoots

d) low auxin:cytokinin ratios stimulated the formation of roots

which of the following combination is correct about the ratio of auxin to cytokinin

#Question id: 4341

#Unit 3. Fundamental Processes

Suppose an experimenter becomes proficient with a technique that allows her to move DNA sequences within a prokaryotic genome. If a researcher moves the promoter for the lac operon to the region between the beta galactosidase (lacZ) gene and the permease (lacY) gene, which of the following results would be most likely?

#Question id: 4342

#Unit 3. Fundamental Processes

Suppose an experimenter becomes proficient with a technique that allows her to move DNA sequences within a prokaryotic genome. If a researcher moves the operator to the far end of the operon, past the transacetylase (lacA) gene, which of the following processes would likely occur when the cell is exposed to lactose?

#Question id: 4343

#Unit 3. Fundamental Processes

Suppose an experimenter becomes proficient with a technique that allows her to move DNA sequences within a prokaryotic genome. If a researcher moves the repressor gene (lacI), along with its promoter, to a position at some several thousand base pairs away from its normal position, which of the following results would be expected?

#Question id: 4344

#Unit 3. Fundamental Processes

How does the transcription of structural genes in an inducible operon occur?

#Question id: 4345

#Unit 3. Fundamental Processes

For a repressible operon to be transcribed, which of the following conditions must occur?

#Question id: 4346

#Unit 3. Fundamental Processes

Which of the following results would occur if the repressor of an inducible operon were mutated so that it could not bind the operator?