In this task, you are given a sentence in the Spanish language. Your task is to translate the Spanish sentence into the English language.

Unen a las células epiteliales entre sí
They join the epithelial cells to each other

Un aumento de ACTH estimula la síntesis y liberación de
An increase in ACTH stimulates the synthesis and release of

Qué aminoácido es precursor de neurotransmisiones como dopamina, adrenalina y noradrenalina?

Which amino acid is a precursor of neurotransmissions such as dopamine, adrenaline and noradrenaline ?