What type of digestion breaks down macromolecules into monomers?

Chemical digestion is the process responsible for breaking down macromolecules into their monomer components. This type of digestion involves biochemical reactions facilitated by enzymes, which convert complex molecules like proteins, carbohydrates, and fats into their simpler forms: amino acids, monosaccharides, and fatty acids, respectively.

In the digestive system, enzymes secreted by the salivary glands, stomach, pancreas, and intestinal lining play crucial roles in this process. For example, amylase breaks down starches into sugars, proteases break down proteins into amino acids, and lipases convert fats into fatty acids and glycerol. This breakdown is essential for nutrient absorption, as the body can only absorb these smaller monomers through the intestinal walls.

Mechanical digestion, on the other hand, involves the physical breakdown of food into smaller pieces, which increases the surface area for enzymes to act upon but does not involve chemical transformations. Ingestion refers to the intake of food into the digestive system, while absorption is the process by which nutrients are taken up into the bloodstream from the digestive tract, after digestion has occurred. Each of these processes plays an important role in digestion, but chemical digestion specifically targets the molecular breakdown necessary for nutrient utilization.