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What is Source of norepinephrine is? and explain in detail?
Tyrosine REF: Lehninger Principles of Biochemistry 4th Edition page 440, 678, and 859 "Tyrosine gives rise to a family of catecholamines that includes dopamine, norepinephrine, and epinephrine" "Norepinephrine is synthesized by a series of enzymatic steps in the adrenal medulla and postganglionic neurons of the sympathetic nervous system from the amino acid tyrosine"