Question

Which food molecules are absorbed from the small intestine lumen into the lacteal, the lymphatic capillary located within the villus?

Answer 1

The lacteals in the small intestine absorb dietary lipids such as fatty acids and fat-soluble vitamins, which are transported as chylomicrons through the lymphatic system to the bloodstream.

Step-by-step explanation:

The small intestine plays a crucial role in the digestive system, particularly in the absorption of nutrients. Within the small intestine, structures known as villi greatly increase the surface area for absorption. Each villus contains blood capillaries and a special lymphatic capillary called a lacteal. The primary function of the lacteal is the absorption of lipid-soluble substances from the digested food. These include dietary lipids such as fatty acids as well as fat-soluble vitamins (vitamins A, D, E, and K).

During digestion, triglycerides are broken down and then reassembled within the cells of the small intestine. These reassembled fats are then incorporated with proteins to form chylomicrons, which enter the lacteals. These chylomicrons, suspended within a milky fluid known as chyle, are transported through the lymphatic system, eventually reaching the bloodstream via the thoracic duct.

Answer 2

The food molecules that are absorbed from the small intestine lumen into the lacteal, the lymphatic capillary located within the villus would be the lipids. Most of the dietary lipids are neutral fat or the so-called triglyceride. These are composed of a glycerol backbone wherein each carbon is linked to a fatty acid. In the small intestine, the villi, microvilli and plicae circulares functions to increase the surface ares that is available for the absorption of the nutrients. Each of the villus consists of a network of capillaries and lymphatic vessels which are called the lacteals which is responsible for the absorption of lipids.