Enterokinase is an enzyme produced in the small intestine that plays a crucial role in digestion. It activates trypsinogen, a precursor to the enzyme trypsin, by cleaving it into its active form. This activation is essential for the digestion of proteins, as trypsin further activates other digestive enzymes. The secretion of enterokinase is stimulated by the presence of food in the stomach, particularly proteins. Once activated, trypsin helps break down proteins into smaller peptides and amino acids, which can be absorbed by the body. Thus, enterokinase is vital for efficient nutrient absorption.