A : Single DNA depenedent RNA polymerase catalyases transcription of all types of RNA in all except bacteria.
R: Structural genes in bacteria are monocistronic .

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 analyze the given statements, we will break down the assertion and reason step by step.

### Step 1: Analyze the Assertion
**Assertion (A):** "Single DNA dependent RNA polymerase catalyzes transcription of all types of RNA in all except bacteria."

- **Explanation:** In bacteria, there is indeed a single type of RNA polymerase that is responsible for synthesizing all types of RNA (mRNA, tRNA, rRNA). This means that the assertion is incorrect because it states that this is not the case for bacteria, which is false.

### Step 2: Analyze the Reason
**Reason (R):** "Structural genes in bacteria are monocistronic."

- **Explanation:** The statement claims that structural genes in bacteria are monocistronic, which means that each mRNA molecule codes for a single protein. However, in bacteria, most mRNA molecules are actually polycistronic, meaning they can code for multiple proteins. Therefore, this reason is also incorrect.

### Step 3: Conclusion
Both the assertion and the reason are false. Therefore, the correct answer is that both statements are incorrect.

### Final Answer:
Both the assertion and the reason are false.

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