Digestive System Regulation of Digestion

Flashcards covering key concepts from the lecture on the regulation of digestion in the digestive system.

What is the purpose of controlling digestion in the GI tract?

To create conditions that maximize digestion and absorption, and to conserve energy during the post-absorptive phase.

What four activities need to be regulated in digestion?

1. Salivary secretion 2. Gastric juice secretion and stomach motility 3. Secretion of bile and pancreatic juice into the small intestine 4. Movements of the large intestine.

What are the two key systems that mediate digestive reflexes?

The Nervous System and the Endocrine System.

What is the role of the enteric nervous system in digestion?

It controls most gut movements and secretions independently of the central nervous system.

What happens to gastric activity during the cephalic phase?

It occurs before food arrives in the stomach and prepares the stomach for digestion by increasing gastric juice production.

What triggers salivary secretion according to Pavlov's experiments?

The sight, smell, or thought of food can trigger increased salivation.

What three hormones are involved in hormonal control of digestion?

1. Gastrin 2. Cholecystokinin (CCK) 3. Secretin.

What occurs during the intestinal phase of gastric activity?

Chyme gradually leaves the stomach and enters the duodenum, leading to decreased gastric secretion and motility, and increased bile and pancreatic juice secretion.

How does secretin function in digestion?

It increases bicarbonate-rich pancreatic juice secretion to neutralize acidic chyme in the duodenum.

What is the gastrocolic reflex?

Distention of the stomach while eating that triggers powerful contractions in the colon, pushing feces into the rectum.

What are the functions of the gall bladder?

Storage and concentration of bile, and control of bile flow to the duodenum.