Anatomy

Question 1

Give an outline of the key differences between features of the Jejunum and Ileum.

Answer 1

NB:

Peyer’s Patches

Groupings of lymphoid follicles in the mucus membrane that lines your small intestine.

Arcades

A series of anastomosing arterial arches between the arterial branches of the jejunum and ileum.

Vasa recta

Straight capillaries coming off from arcades in the mesentery of the jejunum and ileum, and heading toward the intestines.

Plicae Circulares

The numerous permanent crescentic folds of mucous membrane found in the small intestine

(also called valvulae conniventes).

Question 2

What is the Mesentery, and what are its contents?

Answer 2

The mesentery is a double fold of peritoneal tissue that suspends the small intestine and large intestine from the posterior abdominal wall.

Its contents include:

• Superior Mesenteric Artery
• Superior Mesenteric Vein
• Lymph Nodes
• Fat
• Autonomic nerves

Question 3

What are the approximate lengths of the Jejunum and Ileum?

Answer 3

Jejunum: 2.5 m

Ileum: 3.5 m

Question 4

What are the 6 sections of the mesentery?

Answer 4

Question 5

Which organs are intraperitoneal and which are retroperitoneal?

Answer 5

Intra:

Stomach

Appendix

Spleen

Pancreas (tail)

Liver

Duodenum (except for D2-D3)

Jejunum

Ileum

Transverse Colon

Sigmoid Colon.

Rectum (upper ⅓)

Retro: (see picture)

NB:

Primary Retro organs developed and remain outside of the parietal peritoneum.

Secondary Retro organs were initially intraperitoneal, suspended by mesentery. Through the course of embryogenesis, they became retroperitoneal as their mesentery fused with the posterior abdominal wall. Thus, in adults, only their anterior surface is covered with peritoneum.

Question 6

Draw a diagram of the Large Intestine

Answer 6

Also note there should be a Ileal orifice at the Ileo-caecal junction

Question 7

What are the different types of appendix location?

Answer 7

Question 8

What and where are the Paracolic gutters, Subhepatic, and Hepatorenal recesses?

Answer 8

Spaces between organs and/or the abdominal wall

Question 9

What is the Greater Omentum?

Answer 9

The greater omentum is the larger of the two peritoneal folds. It consists of a double sheet of peritoneum, folded on itself so that it has four layers.

The two layers of the greater omentum descend from the greater curvature of the stomach and the beginning of the duodenum.

Question 10

Give an overview of the abdominal lymphatic drainage system

Answer 10