Following are key points about the effect of genetic drift:

A. Genetic drift is significant in small populations.

B. Genetic drift can cause allele frequencies to change in a pre-directed way.

C. Genetic drift can lead to a loss of genetic variation within populations.

D. Genetic drift can cause harmful alleles to become fixed.

Which one of the following combination of the above statements are true?

#Question id: 4337

#Unit 3. Fundamental Processes

Which of the following conditions is most likely to cause the lactose operon to be transcribed?

#Question id: 4338

#Unit 3. Fundamental Processes

Altering patterns of gene expression in prokaryotes would most likely serve an organism's survival by __.

#Question id: 4339

#Unit 3. Fundamental Processes

In positive control of several sugar metabolism-related operons, the cAMP receptor protein (CRP) binds to DNA to stimulate transcription. Which of the following environmental conditions causes an increase in CRP activity in stimulating transcription?

#Question id: 4340

#Unit 3. Fundamental Processes

There is a mutation that is found in E. coli in the repressor that results in a molecule known as a super-repressor because it represses the lac operon permanently. Which of the following characteristics would you expect to observe in such a mutant?

#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?