Gastric acid network (called canaliculi) from which the hydrochloric acid is secreted into the lumen of the stomach. The pH of gastric acid is 1.5 to 3.5 in the human stomach lumen, the acidity being maintained by the proton pump H/K ATPase. The parietal cell releases bicarbonate into the bloodstream in the process, which causes a temporary rise of pH in the blood, known as an alkaline tide. The highly acidic environment in the stomach lumen causes proteins from food to lose their characteristic folded structure (or denature). This exposes the protein's peptide bonds. The gastric chief cells of the stomach secrete
What Kate Does What Kate Does "What Kate Does" is the 106th television episode of the American Broadcasting Company's "Lost" and third episode of the sixth season. It was written by executive producers Edward Kitsis and Adam Horowitz and directed in September 2009 by Paul Edwards. "What Kate Does" was first aired February 9, 2010, on ABC in the United States and on CTV in Canada. Kate Austen is the character on whom the episode is centered. In December 2007, Kate Austen chases after James "Sawyer" Ford (Josh Holloway), who escapes from the Others' captivity in the island's temple and is grieving over