Question

1. The stimulus for the secretion of HCl during the cephalic phase of gastric regulation is ________.

   		the hypothalamus
   		the vagal stimulation of chief cells
   		the release of somatostatin by ECL cells
   		the vagal stimulation of parietal cells
   		the release of secretin

2. The large intestines absorb water by the following mechanism:

		active transport
		cotransport
		osmosis
		All of the choices are correct.

Answer 1

1.The stimulus for the secretion of HCL during the cephalic phase of gastric regulation is the vagal stimulation of parietal cells. Parietal cells have cholinergic receptors M3 which cause acid secretion. Vagus activation activates postganglionic parasympathetic neurons in the stomach and induces acetylcholine on parietal cells to induce acid secretion

2.The large intestine absorb water by osmosis.

In response to an osmotic gradient formed by electrolyte absorption, the water diffuses. Sodium is primarily absorbed by sodium channels inside the colon. Potassium is either absorbed or secreted in the lumen depending on the concentration.