Assume that you had radioactivity labeled an amino acid in a

Assume that you had radioactivity labeled an amino acid in a glass of milk. Also assume that you have all the necessary instruments to follow the course of the amino acid throughout the body. Describe the path that would be taken by the amino acid from the mouth to the aorta. In your response, be sure to indicate how the amino acid moves from one area to the next.

Solution

Presumably the amino acid could be in a protein. The milk (with proteins covered) is swallowed, and actions down the esophagus to the stomach. In the belly, it encounters hydrochloric acid and pepsin, both of which generally tend to break down proteins, so the digestive system starts. The stomach contents form acid chyme, that is handed via the pyloric sphincter to the duodenum, the first part of the small gut. There it encounters enteropeptidases and other proteases, which destroy the protein down to amino acids. They are absorbed via the wall of the small gut and pass into the circulatory gadget. Blood includes them from the mesenteric vein to the hepatic portal vein to the inferior vena cava, then thru the coronary heart (right atrium to proper ventricle to pulmonary artery to lungs to pulmonary vein to left atrium to left ventricle) till it is pumped out of the left ventricle to the aorta.