Chemical and mechanical digestion are the two methods your body uses to break down foods. Mechanical digestion involves physical movement to make foods smaller. Chemical digestion uses enzymes to break down food.
Absorption is a process that takes place in the small intestines or ileum of the GI tract, in which simple and soluble nutrients are absorbed into the blood stream.
Absorption is enhanced by several adaptations of the gut such as large surface area of the gut which directly facilitates absorption of nutrients.
Presence of villi and microvilli in the gut increases the surface area for absorption of nutrients in the ileum.