NDA TBL 3 The Physiology of Small Intestinal Motility and Enteric Nervous System (2)

The gastrointestinal smooth muscle functions as a syncytium, meaning that:

Adjacent muscle fibres are electrically connected and act together

Which of the following statements correctly describes slow waves in the gastrointestinal tract?

They are spontaneous oscillations of membrane potential that set rhythm

The spike potentials in intestinal smooth muscle are mainly stimulated by:

Stretch, acetylcholine, and parasympathetic activation

The interstitial cells of Cajal function primarily as:

Electric pacemakers coordinating smooth muscle activity

The tonic contractions of the gastrointestinal tract are mainly found at:

The sphincters

The enteric nervous system is composed of:

The myenteric and submucosal plexuses within the gut wall

The myenteric (Auerbach’s) plexus is located:

Between circular and longitudinal muscle layers

The main function of the myenteric plexus is to:

Control gastrointestinal movements and peristalsis

The submucosal (Meissner’s) plexus primarily controls:

Local secretion and mucosal blood flow

Parasympathetic stimulation of the intestine generally causes:

Increased motility and secretory activity

Which of the following gastrointestinal hormones primarily stimulates gallbladder contraction?

Cholecystokinin (CCK)

Secretin is released in response to:

Acidic chyme entering the duodenum

The principal function of secretin is to:

Promote pancreatic bicarbonate secretion and neutralize acid

Gastric inhibitory peptide (GIP) has which effect on the stomach?

Decreases motor activity and slows gastric emptying

Motilin is secreted mainly during:

Fasting periods between meals

The basic propulsive movement of the gastrointestinal tract is known as:

Peristalsis

The principal stimulus for initiating intestinal peristalsis is:

Distension of the gut wall by luminal contents

Segmental contractions in the small intestine primarily serve to:

Mix intestinal contents for digestion and absorption

Which statement best summarizes the difference between peristalsis and segmentation?

Peristalsis propels contents, segmentation mixes them locally

The term “enteric nervous system” is best defined as:

The intrinsic neural network of the gut wall coordinating digestion