Which sequence describes the correct path of digestion from entry to exit?

Which sequence describes the correct path of digestion from entry to exit?

• A. Mouth for mastication, esophagus, stomach, duodenum, small intestine, large intestine, rectum.
• B. Mouth, esophagus, stomach, colon, rectum, small intestine, duodenum.
• C. Mouth to stomach directly, then duodenum, then colon, then small intestine, then rectum.
• D. Esophagus first, then mouth, then stomach, then duodenum, then small intestine, then large intestine, and finally rectum.

Answer: (A)

Digestive flow starts in the mouth, where chewing and saliva form a bolus that is then carried down the esophagus by rhythmic contractions into the stomach, where mechanical mixing and gastric juices begin breaking things down. From the stomach, chyme moves into the duodenum, the first part of the small intestine, and then continues through the rest of the small intestine where most nutrient absorption occurs, before passing into the large intestine where water is absorbed and waste is formed, finally exiting via the rectum. This sequence—mouth, esophagus, stomach, duodenum, small intestine, large intestine, rectum—matches how food traverses the digestive tract. Sequences that place the colon before the small intestine, or swap the order of swallowing and esophageal transport, would not reflect the true path of digestion.

Digestive flow starts in the mouth, where chewing and saliva form a bolus that is then carried down the esophagus by rhythmic contractions into the stomach, where mechanical mixing and gastric juices begin breaking things down. From the stomach, chyme moves into the duodenum, the first part of the small intestine, and then continues through the rest of the small intestine where most nutrient absorption occurs, before passing into the large intestine where water is absorbed and waste is formed, finally exiting via the rectum. This sequence—mouth, esophagus, stomach, duodenum, small intestine, large intestine, rectum—matches how food traverses the digestive tract. Sequences that place the colon before the small intestine, or swap the order of swallowing and esophageal transport, would not reflect the true path of digestion.