Answer: The stomach secretes water, electrolytes, hydrochloric acid, and glycoproteins, including mucin, intrinsic factor, and enzymes (Fig. 24.3). Gastric motility and secretion are regulated by neural and humoral mechanisms.
Explanation: The gastric mucosa secretes 1.2 to 1.5 liters of gastric juice per day. Gastric juice renders food particles soluble, initiates digestion (particularly of proteins), and converts the gastric contents to a semiliquid mass called chyme, thus preparing it for further digestion in the small intestine.