Which process is characterized by the assimilation of nutrients into the body's tissues?

The process characterized by the assimilation of nutrients into the body's tissues is absorption. During absorption, the digested food nutrients pass through the intestinal lining into the bloodstream or lymphatic system. This allows essential substances like vitamins, minerals, carbohydrates, proteins, and fats to enter the body's tissues, where they can be utilized for energy, growth, and cellular repair.

Once absorbed, these nutrients are transported throughout the body to where they are needed. In contrast, digestion refers to the breakdown of food into smaller, usable components, while transport describes how those components move through the body after absorption. Metabolism encompasses a broader range of biochemical processes, including both catabolic (breaking down molecules for energy) and anabolic (building up molecules for tissue) reactions, but it is absorption that specifically involves the transfer of nutrients from the digestive system into the body's tissues.