1. In the process of physical digestion, the body mechanically decreases food, either by grinding or crushing it into smaller particles. Chemical digestion, on the other hand, modifies the structure of the food, which is comprised up of several linked atoms, by the activity of enzymes—small proteins.
2. The small intestine is in responsible for collecting glucose, amino acids, fatty acids, vitamins, and minerals from food so that they may be used by the body. This function is aided by tiny projections known as villi, which form a microscopic, brush-like lining within the small intestine that acts like a comb, catching vital nutrients from digested food as it exits the stomach.
The diffusion mechanism, aided by water, is critical in nutrient extraction in the small intestine. Diffusion is the chemical mechanism by which water and water-soluble substances are transported over barriers such as the villi in the small intestine. These molecules include a variety of nutrients that the body need.
References:
Sprouse, S. (2022, July 20). Your Guide to How Nutrients are Absorbed by the Body. Ask the Scientists. https://askthescientists.com/nutrient-absorption/