Session 1

Question 1

Name the muscles that form the abdominal wall

Answer 1

External oblique (action ‘hands in pockets’), internal oblique (perpendicular action), transverse abdominus, Rectus abdomius ( tendonous intersections giving rise to ‘six pack’)

Question 2

What is peristalsis and what facilitates this action?

Answer 2

Rapid movement of contents along the gut facilitated by contraction of the muscularis propia

Question 3

What are the 2 main plexuses of the enteric nervous system, where are they and what is their main fucntion?

Answer 3

Meissners Plexus in the Submucosa predominately regulates secretions and blood flow

Auerbachs Plexus is myenteric and mainly controls gut motility

Question 4

What nerves have a parasympathetic effect on the GI system

Answer 4

Vagus and Pelvic nerves

Question 5

What is the action of Cholecystokinin

Answer 5

Produced from I cells in the duodenum and jejunum stimulated by fat and protein. Gall bladder contracts and pancreas stimulated. This releases bile digestive enzymes

Question 6

What is the action of Secretin

Answer 6

When there’s a drop in pH, S cells are stimulated. HCO3 increased and decreases gastric secretions

Question 7

What is the action of Somatostatin

Answer 7

When there’s a low pH, Delta cells release somatostatin. This switches of G cells reducing Gastrin secretion

Question 8

In what layer are lymph capillaries in the gut?

Answer 8

Submucosa

Question 9

What is the relevance of the Arcuate line?

Answer 9

Above the arcuate line, the muscles anterior to rectus abdominus is External Oblique and half of internal oblique.

Below the arcuate line, External oblique, internal oblique and transverse abdominus are all anterior to rectus abdominus