Question

Amino acids are absorbed

• A. by facilitated transport in duodenum and, jejunum
• B. by active transport in duodenum and jejunum
• C. by active transport in jejunum and ileum
• D. by simple diffusion injejunum and ileum

Answer 1

The correct option is B by active transport in duodenum and jejunum

Active transport mechanisms, primarily in the duodenum and jejunum, absorb most proteins as their breakdown products, amino acids. Almost all (95 to 98 percent) protein is digested and absorbed in the small intestine. The type of carrier that transports an amino acid varies. Most carriers are linked to the active transport of sodium. Short chains of two amino acids (dipeptides) or three amino acids (tripeptides) are also transported actively. However, after they enter the absorptive epithelial cells, they are broken down into their amino acids before leaving the cell and entering the capillary blood via diffusion.

So, the correct answer is 'by active transport in duodenum and jejunum'.