It starts in the mouth where saliva containing certain enzymes begin to break down carbohydrates and continues in the stomach and intestines as other enzymes and acid is released as the food progresses through the digestive tract. Absorption takes place mainly in the small intestines, though important nutrients and water are absorbed by the large intestine. Compaction is the job of the large intestines. This makes the feces ready for elimination. Salivary Glands - Secretion of lubricating fluid containing enzymes that breakdown carbohydrates.
Endocrine cells secrete hormones.
There, the break down of major food molecules takes place, lubrication of the food pathway is provided, and control of the acidity of the food released into the small intestines by the stomach is controlled.