Final answer:
Digestion of macronutrients like proteins, fats, and carbohydrates mainly occurs before the chyme reaches the large intestine, with vitamins and leftover water and salts being absorbed there.
Step-by-step explanation:
In the digestive system, different nutrients are digested in different locations. From the entrance of the large intestine, vitamins and any leftover water and salts are absorbed, but it is not a major site for digestion of macronutrients. In fact, most digestion and nutrient absorption occurs before the chyme reaches the large intestine. Carbohydrates begin to be digested in the mouth through the action of amylase, proteins undergo partial digestion in the stomach, and the majority of fat digestion takes place in the small intestine, not the large intestine.