Repeated genes are useful

Options

A. Against mutations
B. Formation of pseudogenes
C. Formation of multiple copies of a product
D. All the above.

Answer

**Step-by-Step Solution:**

1. **Understanding Repeated Genes**:
- Repeated genes, also known as repeated DNA sequences, are segments of DNA that occur multiple times within the genome. They can vary in the number of copies from one chromosome to another.

2. **Analyzing the Options**:
- The question presents four options regarding the usefulness of repeated genes:
- A) Against mutations
- B) Formation of pseudogenes
- C) Formation of multiple copies of a product
- D) All of the above

3. **Evaluating Each Option**:
- **Option A: Against Mutations**:
- Repeated genes can provide a buffer against mutations. If a mutation occurs in one copy, other copies can still function, thus maintaining the overall function of the gene.
- **Option B: Formation of Pseudogenes**:
- Pseudogenes are non-functional sequences that resemble functional genes. They often arise from repeated genes through mutations and can provide insights into evolutionary processes.
- **Option C: Formation of Multiple Copies of a Product**:
- Repeated genes can lead to the production of multiple copies of proteins or other gene products, which can be beneficial for the organism, especially in cases where high levels of a product are necessary.

4. **Conclusion**:
- Since all three options (A, B, and C) are correct regarding the usefulness of repeated genes, the best answer is:
- **D) All of the above**.

**Final Answer**: D) All of the above.

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