Question

1. describe the role of the digestive system in nutrient absorption and its connection to the circulatory system.

Explanation:

The digestive system breaks down food into nutrients (like glucose, amino acids) through mechanical (e.g., chewing) and chemical (e.g., enzymes in stomach and small intestine) processes. The small intestine, with its villi and micro - villi, is the main site of nutrient absorption. These absorbed nutrients then enter the capillaries (in the case of water - soluble nutrients like glucose and amino acids) or lacteals (for fat - soluble nutrients like fatty acids and glycerol packaged as chylomicrons). The capillaries drain into the hepatic portal vein (which takes nutrients to the liver first for processing) and then into the general circulatory system. The lacteals eventually drain into the lymphatic system, which then connects to the circulatory system at the subclavian veins. So, the digestive system provides the nutrients, and the circulatory system transports these nutrients to cells throughout the body for energy production, growth, repair, etc.

Answer:

The digestive system breaks down food into absorbable nutrients. The small intestine (with villi/micro - villi) is key for absorption. Nutrients enter capillaries (water - soluble) or lacteals (fat - soluble). Capillaries connect via hepatic portal vein to liver and then circulatory system; lacteals connect to lymphatic system which merges with circulatory system. Thus, digestive system supplies nutrients, circulatory system distributes them.