Peritoneum

Question 1

What is a mesentery

Answer 1

A double fold of the parietal peritoneum

Question 2

What is the parietal peritoneum sensitive to

Answer 2

Pain, touch, temperature and pressure

Question 3

What innervates the parietal peritoneum

Answer 3

1. Lining lateral and anterior walls = lower 6 thoracic nerves
2. Central part diaphragm = phrenic nerve
3. Pelvic = obturator nerve

Question 4

What is the visceral peritoneum sensitive to

Answer 4

Stretch via ANS afferent fibres

Question 5

Describe an intra-peritoneal structure

Answer 5

One that has mesentery; it is surrounded by peritoneum except at the one point of attachment

Question 6

Describe an extra-peritoneal structure

Answer 6

One that has no mesentery; partially covered in peritoneum as it is stuck to the abdominal wall (behind the peritoneal lining)

Question 7

Describe primary and secondary extra-peritoneum

Answer 7

Primary = never had a mesentery and always been stuck to the abdominal wall
Secondary = developed free from the abdominal wall and then fused post development

Question 8

Describe an infra-peritoneal structure

Answer 8

One that is located inside the pelvic cavity, below the peritoneal lining

Question 9

What is the greater sac

Answer 9

Cavity in the abdomen that is inside the peritoneum, but outside the lesser sac

Question 10

What is the greater omentum

Answer 10

A large apron-like fold of visceral peritoneum

Question 11

Where does the greater omentum hang from and reach to, in the abdomen

Answer 11

It extends from the greater curvature of the stomach, passing in front of the small intestines and doubles back to ascend to the transverse colon, where it reaches the posterior abdominal wall

Question 12

Why is the greater omentum described as the ‘policeman’ of the abdomen

Answer 12

It is found in areas where there are problems; it tries to localise any infections by semi closing off the area to the rest of the abdominal cavity

Question 13

How many layers make up the greater omentum

Answer 13

4

Question 14

What attaches the transverse colon to the abdominal wall

Answer 14

The transverse mesocolon

Question 15

What does the transverse colon divide the peritoneal cavity into

Answer 15

1. Supra-colic compartment (liver, gall bladder, stomach)

2. Infra-colic compartment (intestines)

Question 16

What blood vessels does the GO carry; and where do they originate from

Answer 16

1. Right gastro-omental vessels (from the hepatic artery)

2. Left gastro-omental vessels (splenic artery)

Question 17

What do the vessels in the GO supply

Answer 17

The GO itself, and the curvature of the stomach

Question 18

What is the lesser sac

Answer 18

The portion of the peritoneal cavity located behind the lesser omentum and stomach

Question 19

What is the space between the greater and lesser sacs called

Answer 19

The epiploic (omental) foramen

Question 20

Where does the lesser omentum (LO) hang from and reach to, in the abdomen

Answer 20

It extends from the liver to the lesser curvature of the stomach and the first part of the duodenum

Question 21

How many layers make up the LO

Answer 21

2

Question 22

What are the boundaries of the epiploic foramen

Answer 22

Anterior = LO
Posterior = IVC
Superior = liver

Question 23

What is the function of the mesentery ‘proper’

Answer 23

It carries the vessels, nerves and lymphatics to/from most of the small intestine (jejenum and ileum)

Question 24

What artery connects the superior and inferior mesenteric arteries

Answer 24

The marginal artery of the colon

Question 25

What does the peritoneal fluid provide

Answer 25

A moist and smooth environment for motile activities to take place; it reduces friction and damage