In Phenylketonuria accumulation a phenylanine generally occurs in

Options

A. brain
B. kidney
C. liver
D. skin

Answer

### Step-by-Step Solution:

1. **Understanding Phenylketonuria (PKU)**:
- Phenylketonuria is a genetic disorder caused by the deficiency of the enzyme phenylalanine hydroxylase. This enzyme is crucial for the metabolism of the amino acid phenylalanine.

2. **Role of Phenylalanine Hydroxylase**:
- Normally, phenylalanine is converted into another amino acid called tyrosine by the action of phenylalanine hydroxylase. When this enzyme is absent, phenylalanine cannot be converted and accumulates in the body.

3. **Consequences of Accumulation**:
- The accumulation of phenylalanine leads to the formation of phenyl pyruvic acid, which can be toxic. This toxic substance primarily affects the brain.

4. **Impact on the Brain**:
- The high levels of phenylalanine and its byproducts can lead to neurological issues, including mental retardation, if not managed properly.

5. **Identifying the Correct Answer**:
- Given the options: brain, kidney, liver, or skin, the correct answer is the brain, as this is where the accumulation of phenylalanine occurs and leads to significant health issues.

### Final Answer:
The accumulation of phenylalanine in phenylketonuria generally occurs in the **brain**.

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