After a mutation at a genetic locus the character of an organism changes due to the change in :

Options

A. protein structure
B. DNA replication
C. protein synthesis pattern
D. RNA transcription pattern

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks what changes in an organism's character after a mutation at a genetic locus. We need to identify the biological process that is affected by this mutation.

2. **Central Dogma of Molecular Biology**: Familiarize yourself with the central dogma, which states that DNA is transcribed into RNA, and RNA is translated into protein. This sequence is crucial for understanding how genetic information leads to the expression of traits.

3. **Identifying the Role of Proteins**: Recognize that proteins are the functional molecules in cells that determine the characteristics of an organism. Changes in protein structure can lead to changes in function, which in turn can affect the organism's traits.

4. **Effect of Mutation**: A mutation at a genetic locus means there is a change in the DNA sequence. This can lead to changes in the mRNA produced during transcription and subsequently alter the amino acid sequence of the protein during translation.

5. **Conclusion**: Since the question specifically asks about the change in the character of the organism due to a mutation, the most direct effect of a mutation at a genetic locus is on the protein structure. Therefore, the correct answer is that the character of the organism changes due to the change in protein structure.

**Final Answer**: The character of an organism changes due to the change in protein structure.

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