Question

Deficiency of the enzyme phenylalanine hydroxylase causes Phenylketonuria. Phenylalanine hydroxylase converts phenylalanine to

• A. tryptophan
• B. alanine
• C. tyrosine
• D. threonine

Hint:

In Phenylketonuria, phenylalanine hydroxylase deficiency prevents the conversion of phenylalanine to tyrosine, leading to its accumulation.

Answer 1

The Correct Option is C

Step 1: Understanding the condition.
Phenylketonuria is a metabolic disorder where the body cannot properly convert phenylalanine to tyrosine due to a deficiency in the enzyme phenylalanine hydroxylase.

Step 2: Analyzing the options.
(A) tryptophan: This is incorrect; phenylalanine is not converted to tryptophan.
(B) alanine: This is incorrect; phenylalanine is not converted to alanine.
(C) tyrosine: Correct — phenylalanine is converted to tyrosine by the enzyme phenylalanine hydroxylase.
(D) threonine: This is incorrect; phenylalanine is not converted to threonine.

Step 3: Conclusion.
The correct answer is (C) tyrosine.