Anatomy - Abdomen

Question 1

Four layers of the small intestine.

Answer 1

Adventitia - connective tissue

Muscularis externa:

• outer layer of longitudinal smooth muscle
• myenteric (Auerbach’s plexus)
• inner layer of circular smooth muscle

Submucosa - Meissner’s plexus, vessels, lymphatics, connective tissue

Mucosa:

• muscularis mucosae
• lamina propria - vessels & immune cells
• epithelium

Question 2

Where are Peyer’s patches located?

Answer 2

The ileum.

Peyer’s patches are nodules of lymphoid tissue.

Question 3

The small intestine is 7m long, but has an internal surface area of 250m2. What are the features that create this disparity?

Answer 3

Valvulae conniventes - mucosal folds

Villi - microscopic projections of epithelium

Microvilli ‘brush border’ - crypts within cell surface

Question 4

Name the three vessels in a single villus.

Answer 4

Arteriole (feeds into a tiny capillary bed at tip of villus)
Venule (drains capillary bed back to portal vein)
Lacteal (lymphatic capillary)

Question 5

What is the blood supply to the liver?

Answer 5

Right & left hepatic arteries (~500ml/min) - oxygenation

Portal vein (~1000ml/min) - metabolic functions

Question 6

Describe the morphological anatomy of the liver.

Answer 6

Anatomical right & left lobes as divided by the falciform ligament.

Caudate (posterior)

Quadrate (inferior)

Question 7

Describe the macroscopic functional anatomy of the liver.

Answer 7

The Couinard classification.

Eight lobes with its own branches of hepatic artery, portal vein, hepatic vein and biliary duct.

Start at the caudate lobe 1-8, clockwise.

Also right and left halves as divided by Cantlie’s line (between gallbladder and IVC)