Which of the following is the precursor for adrenaline and thyroxine synthesis?
Harper – 267, 446
Tyrosine is the precursor for triiodothyronine and thyroxine. It is also an immediate precursor for the catecholamines (adrenaline) and tyrosine hydroxylase is the rate limiting enzyme in the catecholamine biosynthesis.
Phenylalanine
Tyrosine
Tryptophan
None of the above