T1 L2 Understanding the peritoneal cavity

Question 1

What are the 3 divisions of the gut?

Answer 1

Foregut
Midgut
Hindgut

Question 2

What organs are in the foregut?

Answer 2

Oesophagus
Stomach
Proximal half duodenum
Liver 
Pancreas

Question 3

What organs are in the midgut?

Answer 3

Distal half of duodenum
Jejunum
Ileum
Cecum
Ascending colon
3/4 of transverse colon

Question 4

What organs are in the handout?

Answer 4

1/4 of transverse colon
Descending colon
Sigmoid colon & rectum

Question 5

What is the definition of peritoneum?

Answer 5

Serous membrane lining the abdominal cavity & investing its viscera

Question 6

What is the mesentery?

Answer 6

Formed by a double layer of peritoneum
Suspends gut organs
Pathway for blood, innervation, lymphatics to reach the gut
Can be dorsal or ventral depending on its relation with respect to the gut tube.

Question 7

What is the ventral mesentery?

Answer 7

Degenerates during development except for the foregut

Question 8

What does the foregut region of the ventral mesentery give rise to?

Answer 8

Ligaments are the liver
Falciform liver
Lesser omentum

Question 9

What does the lesser omentum attach together?

Answer 9

The lesser curvature of the stomach to the back of the liver

Also has a free edge

Question 10

What is the dorsal mesentery?

Answer 10

Attaches gut organs to posterior abdominal wall

Question 11

What does the dorsal mesentery give rise to?

Answer 11

Gastrosplenic ligament
Linenorenal ligament
Greater omentum
Mesentery of small & large intestine

Question 12

What does the gastrosplenic ligament link?

Answer 12

The stomach to the spleen

Question 13

What is the greater omentum?

Answer 13

Bit of fat at the front of the abdomen

Allows things to move against each other without friction to prevent adhesions

Question 14

Describe the abdomen

Answer 14

Trunk below diaphragm
Abdominal cavity = abdominopelvic
Greater pelvis is continuous with lesser pelvis

Question 15

What muscles are found in the anterior abdominal wall?

Answer 15

External oblique
Internal oblique
Transverse abdominis
Rectus abdominis

Question 16

Describe the external oblique

Answer 16

Found in anterior abdominal wall
From outer surface of rib 4 - rib 12
Goes to linea alba, iliac crest & pubic tubercle

Question 17

What is the function of the external oblique?

Answer 17

works with internal oblique for torsional movement of trunk

Question 18

Describe the internal oblique

Answer 18

From lateral 1/3 of inguinal ligament & anterior 2/3 of iliac crest
Goes to linea alba, costal margin & crest of pubic bone

Question 19

What is the function of the internal oblique?

Answer 19

Flexion & rotation of trunk

Compression of viscera

Question 20

What arteries supply the anterior abdominal wall?

Answer 20

Superior & inferior epigastric
Intercostal
Circumflex iliac

Question 21

What veins supply the anterior abdominal wall?

Answer 21

Thoracoepigastric

Question 22

What nerves supply the anterior abdominal wall?

Answer 22

Thoracoabdominal nerves

Question 23

Describe the lesser/greater sacs

Answer 23

Formed as a result of organ rotation
Lesser sac is behind stomach
Rest of peritoneal cavity is greater sac
Communicate via epiploic foramen

Question 24

What is the inguinal canal?

Answer 24

Passageway for spermatic cord to reach the scrotum & round ligament of the uterus to reach labia majora in females
Limited by superficial & deep inguinal rings
Genital nerve travels through this canal - branch from genitofemoral
Other blood & lymphatics also travel through canal

Question 25

Describe the spermatic cord

Answer 25

Consists of vas deferent, gonadal vessels, nerves, lymphatics & cremaster muscle

As it passes through abdominal wall it takes a sleeve of covering from 3 layers:

• transversalis fascia - contributes innermost covering = internal spermatic fascia
• internal oblique - contributes middle covering = cremasteric fascia
• external oblique - contributes outer covering of cord = external spermatic fascia