Final answer:
Nutrients from digested food are absorbed into the bloodstream in the small intestine, where most nutrients pass through epithelial cells and lipids travel through lacteals to enter blood circulation.
Step-by-step explanation:
The nutrients that were broken down from the food we eat are primarily absorbed into the bloodstream in the small intestine. During the absorption process, most nutrients pass from the lumen of the alimentary canal into the blood through the epithelial cells of the mucosa. Lipids, which are types of fats, are absorbed into specialized lymph vessels known as lacteals, and from there, they are transported to the bloodstream. Therefore, the small intestine is crucial for the digestion and absorption processes, making it possible for nutrients to circulate throughout the body.