Question:
Which of the following is(are) INCORRECT in the regulation of the trp operon?
Which of the following is(are) INCORRECT in the regulation of the trp operon?
Show Hint
The tryptophan operon works on negative feedback: high Trp → repression.
Updated On: Dec 14, 2025
- It is an example of a negatively controlled repressible operon
- The amino acid Trp inactivates the repressor
- The amino acid Trp induces the operon
- The repressor binds to the operator in the presence of amino acid Trp
Show Solution
Verified By Collegedunia
The Correct Option is B, C
Solution and Explanation
Step 1: Understand the trp operon.
The trp operon is a negatively controlled repressible operon. When tryptophan levels are high, tryptophan acts as a corepressor.
Step 2: Evaluate each statement.
(A) Correct — It is indeed a negatively controlled repressible operon.
(B) Incorrect — Tryptophan activates the repressor, not inactivates it.
(C) Incorrect — Tryptophan represses the operon; it does not induce it.
(D) Correct — The Trp–repressor complex binds to operator to stop transcription.
Step 3: Conclusion.
Thus, statements (B) and (C) are incorrect.
The trp operon is a negatively controlled repressible operon. When tryptophan levels are high, tryptophan acts as a corepressor.
Step 2: Evaluate each statement.
(A) Correct — It is indeed a negatively controlled repressible operon.
(B) Incorrect — Tryptophan activates the repressor, not inactivates it.
(C) Incorrect — Tryptophan represses the operon; it does not induce it.
(D) Correct — The Trp–repressor complex binds to operator to stop transcription.
Step 3: Conclusion.
Thus, statements (B) and (C) are incorrect.
Was this answer helpful?
0
0
Top IIT JAM BT Biotechnology Questions
- The porphyrin ring (tetrapyrrole structure) is NOT found in functional
- After how many cycles of polymerase chain reaction (PCR), the amplified product of required length is generated for the first time from a chromosomal DNA template?
- In humans, Down syndrome is caused by
- Which one of the following hormones is produced by the adrenal gland?
- What is the ploidy level of a sporophyte in angiosperms?
View More Questions
Top IIT JAM BT Genetics and Evolution Questions
- Bacterial plasmid genes of non-chromosomal origin are associated with
- The population of a bacterial culture increases from one thousand to one billion in five hours. The doubling time of the culture (correct to 1 decimal place) is ............ min.
- The $K_m$ and $v_{max}$ of lactate dehydrogenase for conversion of pyruvate to lactate are 1 mM and 5 nM s$^{-1}$ respectively. At 0.25 mM pyruvate, the velocity of the reaction catalyzed by lactate dehydrogenase is .............. nM s$^{-1}$.
Top IIT JAM BT Questions
- Which one of the following compounds inhibits the polymerization of tubulin to microtubules in animal cells?
- Arrange the following elements in increasing order of their electronegativity according to the Pauling scale
C, Na, Be and Br - Which one of the following is NOT a plant vascular tissue?
- A growing shoot of a germinating seedling encounters an underground obstacle. Which one of the following hormones elicits ‘triple response’ to the underground obstacle?
- Which one of the following pairs of antibodies contains ‘J-chain’ in their multimeric form?
View More Questions