00:01
Hello students, this question is regarding the tryptophan operon.
00:03
We know that tryptophan operon is a repressible operon.
00:14
That means in presence of higher tryptophan, the operon is repressed and the genes are not synthesized.
00:29
As per the given condition in the first question, the correct answer is option d.
00:37
That is a high level of transcription occurs because cell can no longer detect tryptophan levels.
01:09
This happens when there is mutation in the leader sequence because leader sequence regulates when to activate and when to inhibit the operon.
01:20
So, when that is itself mutated, the operon is unable to sense the level of tryptophan.
01:26
So, it's no longer sensitive to tryptophan levels in the cell.
01:30
Therefore, and also the repressor is mutated.
01:34
So, there will be high levels of transcription.
01:37
The next answer is option b...