Question

indicate whether each statement is true or false:

1. the chemical messengers that regulate stomach secretions include the hormones gastrin, secretin, and cholecystokinin, as well as the paracrine chemical messenger histamine. (click to select)
2. in the cephalic phase of gastric regulation action potentials are sent from the medulla oblongata along parasympathetic neurons within the glossopharyngeal nerves to the stomach. (click to select)
3. parasympathetic stimulation of the stomach mucosa results in the release of the neurotransmitter norepinephrine, which increases the secretory activity of the parietal and chief cells. (click to select)
4. fatty acids, other lipids and some protein digestion products in the duodenum and the proximal jejunum initiate the release of the hormone cholecystokinin (click to select)

Explanation:

1. Gastrin, secretin, cholecystokinin (hormones) and histamine (paracrine) do regulate stomach secretions.
2. In cephalic phase, action potentials are sent via vagus (not glossopharyngeal) nerves from medulla oblongata.
3. Parasympathetic stimulation releases acetylcholine (not norepinephrine) to increase parietal and chief cell activity.
4. Fatty acids, lipids, protein digestion products in duodenum and proximal jejunum do initiate cholecystokinin release.

Answer:

1. True
2. False
3. False
4. True