In phenylketonuria, phenylalanine is not degraded because of defective enzyme:
Correct answer: A. Phenylalanine hydroxylase
- A. Phenylalanine hydroxylase
- B. Phenylalanine oxidase
- C. Phenylalanine phosphate
- D. None of these
Explanation
Explanation:Phenylalanine hydroxylase is an enzyme that converts the amino acid phenylalanine to tyrosine. In PKU, genetic mutations result in a deficiency or absence of functional phenylalanine hydroxylase, leading to the buildup of phenylalanine and its by products in the blood and tissues.Phenylalanine oxidase is not a human enzyme and is not involved in the normal metabolism of Phenylalanine.Phenylalanine phosphate is not an enzyme but a metabolic intermediate of phenylalanine that is not directly involved in the pathogenesis of PKU.
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