Where does carbohydrate absorption begin in the human digestive tract?

Digestion is the process of breaking down complex food organic substances into simpler ones:
– carbohydrates for glucose;
– proteins for amino acids;
fats to glycerol and fatty acids.
The main process of absorption of digestive products is observed in the small intestine, the walls of which are covered with microvilli. But, glucose absorption begins in the oral cavity.