GI 1B- Anatomy of GI wall and Regulation

Question 1

The lumen of the GI tract is continuous with the____ _____

Answer 1

External environment

Question 2

Technically the contents within the lumen are considered _____ the body

Answer 2

Outside

Question 3

Gastric juice penetrates the gastric mucosal barrier injuring the gastric wall with enzymes and acidity

Answer 3

Peptic ulcer disease (PUD)

Question 4

Pancreatic juice escapes the pancreas or duodenum causing destruction of pancreatic tissue and hemorrhage.

Answer 4

acute pancreatitis

Question 5

What causes acute pancreatitis

Answer 5

Secretion of pancreatic juice while the pancreatic duct is obstructed

Question 6

Inflammation of the appendix causing the colon wall to tear open, allowing intestinal bacteria to escape to abdominal cavities

Answer 6

Ruptured appendix

Question 7

What are the 4 layers of the GI tract wall?

Answer 7

1. Mucosa
2. Submucosa
3. Muscularis externa
4. Serosa

Question 8

What is the prominent type of self-induced electrical activity of digestive smooth muscle

Answer 8

Slow-wave potential AKA basal electrical rhythm (BER) AKA pacemaker potential AKA The Great Bambino

Question 9

Neurons of the submucosal and myenteric plexuses are often termed___

Answer 9

intrinsic nerve plexus or enteric nervous system (ENS)

Question 10

Extrinsic Nerves

Answer 10

Nerves that originate outside the GI tract and innervate the various GI organs including vagus and pelvic splanchnic

Question 11

The vagus nerve parasympathetically innervates what portion of the GI tract

Answer 11

Upper GI including:
esophagus
stomach
small intestine
ascending colon

Question 12

What nerves innervate the lower GI tract including: anal canal, transverse, descending and sigmoid colons

Answer 12

pelvic nerves (pelvic splanchnic)

Question 13

The majority of post-ganglionic parasympathetic neurons in the GI tract are___ and ___ , while the post ganglionic sympathetic neurons are ___.

Answer 13

parasympathetic- cholinergic and peptidergic

sympathetic- adrenergic

Question 14

What are the three sympathetic ganglia serving the GI tract

Answer 14

1. celiac
2. superior mesenteric
3. inferior mesenteric

Question 15

how can autonomic nerves influence the motility and secretion of the GI tract?

Answer 15

1. modify ongoing activity in the enteric nervous system
2. altering the level of GI hormone secretion
3. acting directly on smooth muscle and glands