Final Answer:
The sequential steps in protein digestion and absorption are as follows:
Ingestion: Consume protein-containing foods.
Digestion in Stomach: Initiate breakdown with gastric acid and pepsin.
Further Digestion in Small Intestine: Use pancreatic enzymes for partial digestion.
Brush Border Enzymes: Complete digestion on the small intestine's surface.
Absorption: Absorb amino acids and small peptides through the intestinal lining.
Transport to Cells: Transport amino acids to cells for utilization.
Step-by-step explanation:
Ingestion: The initial step involves consuming protein-containing foods as part of the diet.
Digestion in Stomach: Once in the stomach, proteins face the action of gastric acid and the enzyme pepsin, initiating the breakdown process.
Further Digestion in Small Intestine: Partially digested proteins move to the small intestine, where pancreatic enzymes contribute to further breakdown.
Brush Border Enzymes: Enzymes on the surface of the small intestine, specifically the brush border, play a crucial role in completing the digestion of proteins into absorbable forms.
Absorption: Amino acids and small peptides are absorbed through the intestinal lining into the bloodstream for transportation.
Transport to Cells: Amino acids are transported via the bloodstream to cells, where they are used for various biological functions, including the synthesis of new proteins.