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
Break key scancodes at all on release; therefore it is not possible for any software to determine whether this key is being held down. On modern keyboards, the key is usually labeled "Pause" with "Break" below, sometimes separated by a line: formula_1, or "Pause" on the top of the keycap and "Break" on the front. In most Windows environments, the key combination brings up the system properties. Compact and notebook keyboards often do not have a dedicated key. These may use the following substitutes for : Substitutes for : Apple keyboards do not have the Pause/Break key, as Mac OS X does