Gastric acid that it does not become too acidic. These cells also produce mucus, which forms a viscous physical barrier to prevent gastric acid from damaging the stomach. The pancreas further produces large amounts of bicarbonate and secretes bicarbonate through the pancreatic duct to the duodenum to completely neutralize any gastric acid that passes further down into the digestive tract. The main constituent of gastric acid is hydrochloric acid which is produced by parietal cells (also called oxyntic cells) in the gastric glands in the stomach. Its secretion is a complex and relatively energetically expensive process. Parietal cells contain an extensive secretory
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