Final answer:
A mutation in the multimerization domain of Lac repressor that prevents multimerization would result in an increase in the transcription of the lac operon and a decrease in the number of repressor dimers in the cell. Therefore, the correct options from the given choices are: a) Transcription of the lac operon would increase and b) The number of repressor dimers in the cell would decrease.
Step-by-step explanation:
When there is a mutation in the multimerization domain of the Lac repressor that prevents multimerization, it would lead to an increase in the transcription of the lac operon. This is because the repressor protein usually binds to the operator sequence of the lac operon, preventing transcription.
However, when the repressor is unable to multimerize due to the mutation, it cannot effectively bind to the operator, resulting in increased transcription of the lac operon.
Additionally, the number of repressor dimers in the cell would decrease as a result of the mutation. Repressor dimers are formed when multiple Lac repressor proteins come together to bind to the operator and prevent transcription. Without multimerization, there would be fewer repressor dimers in the cell, further contributing to increased transcription of the lac operon.
Therefore, the correct options from the given choices are:
a) Transcription of the lac operon would increase.
b) The number of repressor dimers in the cell would decrease.