Which of the following is a true statement about the digestion and absorption of proteins?
A) Polypeptide chains are digested to yield individual amino acids, which can be absorbed into the blood.
B) Polypeptide chains are digested to yield dipeptides, which can be absorbed into the blood.
C) Many whole proteins are absorbed by phagocytosis and enter the blood.
D) The products of protein digestion are first absorbed into the lymphatic system, which empties into the blood.

Question

Quizplus · Accepted Answer

Proteins are broken down in the small intestine by enzymes called proteases, which break the peptide bonds between amino acids. This results in the formation of smaller peptide fragments, which are further broken down by other proteases until individual amino acids are released. These amino acids can then be absorbed into the bloodstream and transported to the liver and other body tissues to be used for protein synthesis. Dipeptides can also be absorbed into the bloodstream, but they are further broken down into individual amino acids within the cells lining the small intestine before being released into the blood. Phagocytosis is not a primary method of protein absorption. The products of protein digestion are first absorbed into the bloodstream, not the lymphatic system.

Which of the Following Is a True Statement About the Digestion