Theme 1 - Lecture 2 Peritoneal cavity

Question 1

Endoderm

Answer 1

Majority of gut, including most of epithelium and glands of digestive tract

Question 2

Mesoderm

Answer 2

Muscular layers

Question 3

Ectoderm

Answer 3

Epithelium at extremities of tract(cranial and caudal)

Question 4

What is the primitive gut formed as a result of?

Answer 4

• Cranial-caudal

- Lateral

Question 5

Which membranes close the cranial and caudal ends at 4 weeks

Answer 5

• Bucco-pharyngeal

- Cloacal

Question 6

What does the foregut contain?

Answer 6

• Oesophagus
• Stomach
• Proximal half duodenum
• Liver
• Pancreas

Question 7

What does the midgut contain?

Answer 7

• Distal half duodenum
• Jejunum
• Ileum
• Cecum
• Asc +3/4 transv.colon

Question 8

What does the hindgut contain?

Answer 8

• 1/4 transv + desc + sigmoid colon and rectum

Question 9

What is a mesentery?

Answer 9

Formed by a double layer of peritoneum

Question 10

Purpose of mesentery?

Answer 10

• Suspends gut organs
• Pathway for blood, innervation, lymphatics etc to reach the gut
• Ventral mesentery degenerates during development, except for foregut

Question 11

What does the dorsal mesentery give rise to?

Answer 11

• Gastrosplenic ligament
• Lienorenal ligament
• Greater omentum
• Mesentery of small and large intestine

Question 12

What does the ventral mesentery give rise to?

Answer 12

(foregut)
Ligaments around the liver
Falciform ligament
Lesser omentum

Question 13

Describe lesser omentum

Answer 13

• Attaches lesser curvature stomach to back of liver

- Has a free edge

Question 14

Where does inguinal ligament attach from and to?

Answer 14

From ASIS to pubic tubercle

Question 15

What are the attachments of the external oblique?

Answer 15

• Originates from ribs 5-12, and

- Inserts into iliac crest and pubic tubercle

Question 16

Movement of external oblique

Answer 16

• Contralateral rotation of the torso

Question 17

Innervation of the external oblique

Answer 17

• thoracoabdominal nerves (T7-T11) and subcostal nerve(T12)

Question 18

What are the attachments of the internal oblique?

Answer 18

• Originates from the inguinal ligament, iliac crest and lumbodorsal fascia
• inserts into ribs 10-12

Question 19

Internal oblique function

Answer 19

• Bilateral contraction compresses the abdomen, while unilateral contraction ipsilaterally rotates the torso

Question 20

Innervation of intenal obliques

Answer 20

• Thoracoabdominal nerves(T7-T11)
• Subcostal nerve(T12)
• Branches of lumbar plexus

Question 21

Directions of the fibres of internal and external obliques

Answer 21

Internal - Supero-medial

External - Infero-medial

Question 22

Most superficial anterior muscle

Answer 22

• External oblique

Question 23

Location of internal oblique with respect to the other muscles

Answer 23

• Lies deep to the external oblique

- It is smaller and thinner in structure

Question 24

Attachments of the transversus abdominis

Answer 24

• Originates from the inguinal ligament, costal cartilages 7-12, the iliac crest and the thoracolumbar fascia
• Inserts into the conjoint tendon, xiphoid process, linea alba and the pubic crest

Question 25

Function of transversus abdominis

Answer 25

Compression of abdominal contents

Question 26

Innervation of transversus abdominis

Answer 26

- Thoracoabdominal nerves(T7-T11) - Subcostal nerve(T12) - Branches of the lumbar plexus

Question 27

Fascia that is deep to the transversus abdominis

Answer 27

Transversalis fascia

Question 28

What are the attachments of the rectus abdominis

Answer 28

- Originates from the crest of the pubis | - Inserts into the xiphoid process of the sternum and the costal cartilage of ribs 5-7

Question 29

Functions of the rectus abdominis

Answer 29

- Assists the flat muscles in compressing the abdominal viscera, the rectus abdominis also stabilises the pelvis during walking, and depresses the ribs

Question 30

Innervation of the rectus abdominis

Answer 30

Thoracoabdominal nerves(T7-T11)

Question 31

What gives rise to the six pack

Answer 31

- At several places, the rectus abdominis is intersected by fibrous strips, known as tendinous intersections

Question 32

Describe the pyramidalis

Answer 32

Is a small triangular muscle, found superficially to the rectus abdominis It is located inferiorly with its base on the pubis bone, and the apex of the triangle attached to the linea alba

Question 33

Attachments of the pyramidalis

Answer 33

- Originates from the pubic crest and pubic symphysis before inserting into the linea alba

Question 34

Functions of the pyramidalis

Answer 34

- Acts to tense the linea alba

Question 35

Innervation of the pyramidalis

Answer 35

- Subcostal nerve(T12)