TASK DEFINITION: In this task, you are given a sentence in the Spanish language. Your task is to translate the Spanish sentence into the English language.
PROBLEM: ¿Cuál      de estos enunciados NO es una característica de los ensayos clínicos fase I?

SOLUTION: Which of these statements is NOT a characteristic of phase I clinical trials?

PROBLEM: La vía óptica decusa parcialmente en

SOLUTION: The optical path partially decimates in

PROBLEM: ¿Qué aminoácido sirve de partida para la síntesis de porfirinas (grupo hemo)?

SOLUTION:
Which amino acid serves as a starting point for the synthesis of porphyrins (heme group)?