A: Operator gene is functional when it is not blocked by repressor.
R: Regulator gene produces active protein only which acts on operon system in E.coil.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark
B. If both Assertion & Reason are true and the reason is not the correct explanation of the assertion , then mark
C. If Assertion is ture statement but Reason is false, then mark.
D. If both Assertion and Reason are false statements, then mark.

Answer

To solve the assertion and reason question, we will analyze both statements step by step.

### Step 1: Understand the Assertion
The assertion states: "Operator gene is functional when it is not blocked by repressor."
- The operator gene is a segment of DNA that acts as a binding site for a repressor protein.
- When the repressor is bound to the operator, it prevents RNA polymerase from transcribing the downstream genes, effectively blocking gene expression.
- Therefore, when the repressor is not bound to the operator, the operator gene is functional, allowing transcription to occur.

**Conclusion for Assertion**: The assertion is true.

### Step 2: Understand the Reason
The reason states: "Regulator gene produces active protein only which acts on operon system in E. coli."
- The regulator gene does produce proteins (such as repressors or activators) that interact with the operon.
- However, the statement claims that it produces "active protein only," which is misleading. Regulator genes can produce both active and inactive forms of proteins depending on the cellular conditions.
- Additionally, while the operon system is well-studied in E. coli, operons are also found in other organisms, including various bacteria and even some eukaryotes. Thus, the statement is overly restrictive.

**Conclusion for Reason**: The reason is false.

### Final Conclusion
- The assertion is true, while the reason is false. Therefore, the correct answer to the question is that the assertion is true and the reason is false.

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