Question: how are the tyrosine hormones different?
Answer: Amino Acid Derivatives There are two groups of hormones derived from the amino acid tyrosine: Thyroid hormones are basically a "double" tyrosine with the critical incorporation of 3 or 4 iodine atoms. Catecholamines include epinephrine and norepinephrine, which are used as both hormones and neurotransmitters.