In: Anatomy and Physiology
Which phase of gastric secretion is correctly matched with its description?
Group of answer choices
gastric phase — provides about 2/3 of the gastric juice released
cephalic phase — vagus nerve sends action potentials to the stomach
gastric phase — begins when food moves through the gastroesophageal sphincter
intestinal phase — cholecystokinin stimulates secretion of the gastric glands
The correct pair is (b) cephalic phase- vagus nerve sends action potential to the stomach.
There are three phases of gastric acid secretion. These are cephalic phase, gastric phase, and intestinal phase.
The following table shows the features of the three phases.
FEATURES | CEPHALIC PHASE | GASTRIC PHASE | INTESTINAL PHASE |
---|---|---|---|
Occurrence of the phase | Occurs before the food enters the stomach due to smell, sight, etc ( psychic stimulation) | This occurs when food is present in the stomach. | Occurs when the food is duodenum |
Influences | Mainly secreted because of vagus nerve action. Sight and smell of food stimulates the medulla oblongata. This directs the vagus nerve to send more and more action potentials to the enteric plexuses. Hence gastric acid is released. | Local reflexes and response to gastrin. Here mechanoreceptors play a major role by detecting the stretch stimuli of the stomach due to food. | Chemoreceptors and hormonal feedback. |
Amount | 30-50% | 50-60% | very less |
Other statements are wrong because