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Assertion : A change in nitrogen bass at...

Assertion : A change in nitrogen bass at the third position of a codon causes change in the expression of the codon.
Reason : A codon is mostly read by all the three nitrogen bases.

A

If both assertion and reason are true and reason is the correct explanation of assertion

B

If both assertion and reason are true but reason is not the correct explanation of assertion

C

If assertion is true but reason is false

D

if both assertion and reason are false.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze the assertion and reason provided. ### Step-by-Step Solution: 1. **Understanding the Assertion**: - The assertion states that a change in the nitrogen base at the third position of a codon causes a change in the expression of the codon. - In molecular biology, codons are sequences of three nucleotides that correspond to specific amino acids. The third position of a codon is known to be less critical in determining the amino acid due to the wobble hypothesis. 2. **Understanding the Wobble Hypothesis**: - According to the wobble hypothesis, the first two bases of a codon pair precisely with the corresponding bases of the tRNA anticodon. However, the third base can vary without affecting the amino acid that is incorporated during protein synthesis. - This means that a change in the third base often does not lead to a change in the amino acid, hence not affecting the expression of the codon. 3. **Evaluating the Reason**: - The reason states that a codon is mostly read by all three nitrogen bases. - This is misleading because, as per the wobble hypothesis, it is primarily the first two bases that are crucial for the correct pairing with tRNA. The third base can be ambiguous and does not always affect the codon’s meaning. 4. **Conclusion**: - Since the assertion is incorrect (a change in the third base does not typically change the expression of the codon) and the reason is also incorrect (not all three bases are read with equal precision), we conclude that both the assertion and reason are false. 5. **Final Answer**: - Therefore, the correct answer is that both the assertion and reason are false.
To solve the question, we need to analyze the assertion and reason provided. ### Step-by-Step Solution: 1. **Understanding the Assertion**: - The assertion states that a change in the nitrogen base at the third position of a codon causes a change in the expression of the codon. - In molecular biology, codons are sequences of three nucleotides that correspond to specific amino acids. The third position of a codon is known to be less critical in determining the amino acid due to the wobble hypothesis. ...
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