Question: Which of the following substance is the first precursor of adrenaline formation?
A Tyrosine
B Dopamine
C Norepinephrine
D Serotonin
Answer: Tyrosine
| Precursors involved in adrenaline formation | Chemical Formula | Name of enzyme involved | Reaction | Product formed | |
| 1st | Tyrosine | C9H11NO3 | Hydroxylase | Hydroxylation of tyrosine. | Levodopa |
| 2nd | L-DOPA | C9H11NO4 | Decarboxylase | Decarboxylation of L-DOPA | Dopamine |
| 3rd | Dopamine | C8H11NO2 | Hydroxylase | Hydroxylation of dopamine | Norepinephrine (Noradrenaline) |
| 4th | Norepinephrine | C8H11NO3 | Methyltransferase | Methylation of norepinephrine | Adrenaline (Epinephrine) |