Adrenaline, also known as epinephrine, is synthesized from the amino acid tyrosine.

Here's a simplified breakdown of the process:

1. Tyrosine is converted into L-DOPA by the enzyme tyrosine hydroxylase.

2. L-DOPA is then converted into dopamine by the enzyme aromatic L-amino acid decarboxylase.

3. Dopamine is converted into norepinephrine by the enzyme dopamine beta-hydroxylase.

4. Finally, norepinephrine is converted into adrenaline by the enzyme phenylethanolamine N-methyltransferase (PNMT).

This synthesis takes place primarily in the adrenal medulla, a part of the adrenal glands located above the kidneys.