Defects in Which of the Following May Result in Elevated

question 71

Multiple Choice

Defects in which of the following may result in elevated levels of phenylalanine?

• A) deficiencies in dihydropteridine reductase
• B) deficiencies in 4a-carbinolamine dehydratase
• C) defects in the biosynthesis of tetrahydrobiopterin
• D) All of the above

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Definitions:

Amides

Organic compounds containing a carbonyl group linked to a nitrogen atom from an amine, fundamental in the structure of proteins.

Organic Product

A chemical compound of carbon, often produced or derived from living organisms, excluding compounds like carbonates, carbides, and cyanides.

Reaction Sequence

A series of chemical reactions where the product of one reaction becomes the reactant in the next.

Organic Product

A compound or substance that has been prepared or is obtainable by chemical reactions involving organic precursors.