What does the large intestine do?

• A. Water reabsorption
• B. Digestion and nutrient absorption
• C. Production of enzymes
• D. Absorption of bile acids

Answer: (A)

The large intestine primarily reclaims water from indigestible material. After most nutrients have already been absorbed in the small intestine, the large intestine pulls water and electrolytes from what remains, which concentrates the waste into solid feces and helps keep you hydrated. While the colon hosts bacteria that ferment some leftovers and can synthesize certain vitamins, it does not specialize in digesting food or absorbing nutrients. The breakdown and absorption of nutrients occur mainly in the small intestine, with digestive enzymes coming from the pancreas and intestinal lining. Bile acids are reabsorbed mostly in the ileum, not in the large intestine, so this isn’t the colon’s main job.