Digestion 0.5% hydrochloric acid (HCl), which lowers the pH to the desired pH of 1-3. Acid release is also triggered by acetylcholine and histamine. The intestinal phase has two parts, the excitatory and the inhibitory. Partially digested food fills the duodenum. This triggers intestinal gastrin to be released. Enterogastric reflex inhibits vagal nuclei, activating sympathetic fibers causing the pyloric sphincter to tighten to prevent more food from entering, and inhibits local reflexes. Protein digestion occurs in the stomach and duodenum in which 3 main enzymes, pepsin secreted by the stomach and trypsin and chymotrypsin secreted by the pancreas, break down food
Xeno nucleic acid theory of XNA utilization is its incorporation into medicine as a disease-fighting agent. Some enzymes and antibodies that are currently administered for various disease treatments are broken down too quickly in the stomach or bloodstream. Because XNA is foreign and because it is believed that humans have not yet evolved the enzymes to break them down, XNAs may be able to serve as a more durable counterpart to the DNA and RNA-based treatment methodologies that are currently in use. Experiments with XNA have already allowed for the replacement and enlargement of this genetic alphabet, and XNAs have shown complementarity with