Question

Which of the following statements is correct concerning operon gene control? Positive control requires an activator protein to stimulate transcription of the structural genes within an operon. In negative control, a repressor protein inhibits or turns off transcription of the structural genes within the operon. An inducible operon normally is not transcribed. It requires an inducer molecule to stimulate transcription either by inactivating a repressor protein in a negative inducible operon or by stimulating the activator protein in a positive inducible operon. Transcription normally occurs in a repressible operon and transcription is turned off either by the repressor becoming active in a negative repressible operon or by the activator becoming inactive in a positive repressible operon. All of the above statements are correct.

Answer 1

1.e) All of the statements are correct
For positive control, transcription should always happen. So, it requires an activator. And for the negative control, a repressor is required or repressing the transcription. An inducible operon usually requires an inducer protein to activate the operon. Transcription in an operon can be stoped by repressor activation or by activator inactivation.
2. b) RNA interference
RNA interference (RNAi) is a technique used to knock down the expression of mRNA molecules by bind of small RNA molecules like siRNA.
3.d) 5 'TCGGCAT 3'
After the dideoxy sequencing/Sanger sequencing gel pattern is obtained, the sequence is read from the bottom of the gel to the top. So here, first base is A, and the sequenced obtained is 3 'AGCCGTA 5'. But here, we need to find the complement of this sequence. So the answer is 5 'TCGGCAT 3'