Question

please answer both

Which of the following statements is true? The H+/K+-ATPase (proton pump) generates ATP as hydrogen ions are pumped out of parietal cells. Parietal cells of the stomach produce and release hydrochloric and nitric acid. Parietal cells of the stomach exchange sodium for potassium in order to maintain homeostasis prior to stimulation. When a histamine receptor antagonist is presented to parietal cells, followed by histamine, the internal pH of the parietal cells increases dramatically.

Answer 1

1. Answer (D) : When a histamine antagonist present to parietal cells followed by histamine, the internal pH of parietal cells increases dramatically.

Histamine receptor antagonists blocks the release of H+ ions into the deodenum while the histamine triggers sythesis of H+ leads to accumulation of H+ inside the parietal cell increases its internal pH.

2. Answer: (D)

HCL secretion by parietal cells rely on cells of digestive system and also the nervous system. HCL secretion by parietal cells are triggered by gastrinsecretion by G cells upon activation by nerve and the histamine secreted by ECL cells which also innervated by nerve impulse. Parietal cells can also secrete HCL by direct innervation of nerves.