Protein Digestion & Amino Acid Absorption

This simulator renders a section of small intestine in 3D and models, particle by particle, what happens to the protein in a meal. Peptide chains (strings of amino-acid beads) tumble through the lumen while digestive enzyme particles randomly encounter and cleave their peptide bonds, shortening each chain until only free amino acids remain. Those free amino acids drift toward the intestinal wall, where a limited pool of carrier transporters absorbs them into the bloodstream following real Michaelis-Menten saturation kinetics — the same mathematics that governs carrier-mediated nutrient transport throughout physiology. Adjust the meal size, enzyme activity and transporter capacity to see how digestion speed and absorption saturation shape the rise and fall of the plasma amino acid pool after a meal.