Where does digestion begin?

Where does digestion begin?

• A. The mouth
• B. The stomach
• C. The small intestine
• D. The esophagus

Answer: (A)

Digestion begins in the mouth, where both physical and chemical processes start breaking down food. Chewing grinds food into smaller pieces, increasing surface area and forming a manageable bolus that’s easier to swallow. At the same time, saliva is released and contains enzymes—most notably salivary amylase—that start breaking down starch into simpler sugars. Saliva also lubricates the food for easier passage down the esophagus. So, the very first chemical breakdown of nutrients happens here, before any digestion occurs in the stomach or intestines. The esophagus mainly moves the bolus toward the stomach, while the stomach and small intestine carry out the subsequent stages of digestion.

Digestion begins in the mouth, where both physical and chemical processes start breaking down food. Chewing grinds food into smaller pieces, increasing surface area and forming a manageable bolus that’s easier to swallow. At the same time, saliva is released and contains enzymes—most notably salivary amylase—that start breaking down starch into simpler sugars. Saliva also lubricates the food for easier passage down the esophagus. So, the very first chemical breakdown of nutrients happens here, before any digestion occurs in the stomach or intestines. The esophagus mainly moves the bolus toward the stomach, while the stomach and small intestine carry out the subsequent stages of digestion.