Midgut

Question 1

What marks the boundary between the foregut & midgut?

Answer 1

Major duodenal papilla (in 2nd part of duodenum)
-Where bile & pancreatic secretions enter

Question 2

Why does the major duodenal papilla mark the boundary between the foregut & midgut?

Answer 2

Change in vasculature (blood supply) from the superior pancreaticoduodenal artery to the inferior pancreaticoduodenal artery

Question 3

Where is the boundary between the midgut & hindgut?

Answer 3

2/3 along transverse colon

Question 4

Why is 2/3 along transverse colon the boundary of midgut & hindgut?

Answer 4

Change in vasculature (blood supply) from middle colic to 1st branch of inf mes artery (starting here)

Question 5

Role of the appendix?

Answer 5

-Has surrounding lymphoid tissue - MALT
-Filled w/ all gut bacteria -> can repopulate gut bact if had D&V

Question 6

What are the components of the midgut?

Answer 6

Duodenum (distal 2nd half & rest)
Jejunum
Ileum
Cecum (part of LI)
Appendix
Asc colon
Trans colon

Question 7

What is between the ileum & cecum?

Answer 7

Ileocecal valve/junction

Question 8

Role of the ileocecal valve?

Answer 8

Passive - stops reflux into ileum during peristalsis
-Made of smooth muscle

Question 9

Differences between jejunum & ileum?

Answer 9

Question 10

Differences between SI & LI?

Answer 10

Question 11

What vertebral level does the superior mesenteric artery start at?

Answer 11

L1

Question 12

What are omental appendices?

Answer 12

Bits of peritoneum from LI - contains fat & lymphoid tissue

Question 13

What are teniae coli?

Answer 13

x3 strips of muscle (mesecolic, free, omental) -> positioned longitudinally over colon surface

Question 14

What are haustra?

Answer 14

Sacculations caused by the contraction of teniae coli

Question 15

Where do the omental appendices, teniae coli, haustra stop in LI?

Answer 15

At rectosigmoid junction = where smooth muscle of teniae coli forms full layer in rectum

Question 16

Where is the ileum?

Answer 16

Question 17

Where is the jejunum?

Answer 17

Question 18

Where is the duodenum?

Answer 18

Question 19

Where is the caecum?

Answer 19

Question 20

Label this.

Answer 20

Question 21

What is the mesoappendix?

Answer 21

Double layer of peritoneum encasing the appendix (form of mesentery)

Question 22

Where is the mesoappendix?

Answer 22

Question 23

Where is the rectum?

Answer 23

Question 24

Label:
-Coeliac trunk
-Superior mesenteric artery
-Abdominal aorta
-Inferior mesenteric artery

Answer 24

Coeliac trunk = B
Superior mesenteric artery = C
Abdominal aorta = A
Inferior mesenteric artery = G

Question 25

In which abdominal region is the appendix found?

Answer 25

Right iliac

Question 26

Which of the following mid gut organs has a mesentery?

Answer 26

Ileum

Question 27

Label this.

Answer 27

Question 28

What is the fan-shaped projection of peritoneum that connects the small intestine to the posterior abdominal wall known as?

Answer 28

Mesentery

Question 29

Label this.

Answer 29

Question 30

Which is the stomach, jejunum & ileum?

Answer 30

A = Stomach
B = Ileum
C = Jejunum

Question 31

Which label indicates the body of the pancreas?

Answer 31

H

Question 32

Which label indicates the superior mesenteric artery?

Answer 32

D

Question 33

Which label indicates the gastroduodenal artery (which gives origin to both the anterior and posterior superior pancreaticoduodenal arteries)?

Answer 33

G