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Flashcards in midgut and hindgut Deck (73)
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1
Q

where does the foregut range from?

A

From esophagus to D3/D4 segment of the duodenum

2
Q

where does the midgut range from?

A

D4 Segment (transition portion), Jejunum, ileum, cecum, ascending and first 2/3 of the transverse colon

3
Q

where does the hindgut range from?

A

Distal 1/3 transverse colon, descending colon, sigmoid colon, rectum

4
Q

how long is the SI?

A

6-7m

5
Q

how long is the duodenum?

A

20-25 cm

6
Q

what type of organs are the ileum and jejunum?

A

intraperitoneal organ

7
Q

what suspends the ileum and jejunum to the posterior abdominal wall?

A

mesentery proper

8
Q

what travels within the mesentery proper?

A

vessels

9
Q

what is prominently found in the jejunum which is not as prominent even absent in the ileum? what is its function?

A

plicae circulares

function; increases surface area and allows for maximal absorption

10
Q

how could the wall of the jejeunum be described?

A

thicker and more red in color

11
Q

how can the vessels of the jejunum be described as?

A
  • long vasa recta vessels (straight)

- few vascular arcades (loops)

12
Q

where is the jejunum located anatomically

A

in the LUQ

13
Q

how can the wall of the ileum be described as?

A

thinner, whiter in color due to less vessels

14
Q

how could the vessels of the ileum be described?

A

short vasa recta

many large vascular arcades

15
Q

what is present exclusively in the ileum and served to filter fluids?

A

Peyer’s patch which are lymphatic aggregates

16
Q

where is the ileum located anatomically?

A

RLQ

17
Q

how long is the colon

A

~1.5m

18
Q

where does the colon range from

A

ileocecal junction to the anus

19
Q

how does the ileocecal valve differ from other sphincters?

A

Ileocecal valve uses pressure differentials as opposed to actual motor activity like most sphincters

20
Q

what part of the colon is jointed to the left by the ileum?

A

cecum

21
Q

what is the cecum?

A

Blind-ended pouch located in the lower right quadrant

22
Q

what is contained in the cecum of the colon that serves as an extension?

A

appendix

23
Q

what is the appendix?

A

narrow blind ended tube

24
Q

what type of organ is the appendix?

A

intraperitoneal

25
Q

if we refer to the appendix being found post-ileal what does it mean?

A

behind the ileum

26
Q

if we refer to the appendix being found retroceccal what does it mean?

A

behind cecum

27
Q

if we refer to the appendix being found subcecal what does it mean?

A

under the cecum

28
Q

if we refer to the appendix being found in the pelvic what does it mean?

A

pointing towards the pelvis

29
Q

if we refer to the appendix being found pre/sub-ileal what does it mean?

A

infront of the ileum

30
Q

where is the appendix located?

A

at McBurnery’s point

measures from the Right ASIS to the umbilicus, at the lateral 1/3

31
Q

what type of organ is the ascending colon?

A

retroperitoneal organ

32
Q

where does the ascending colon extend from?

A

Extends superiorly from the cecum to the liver

33
Q

where does the acending colon transition into the transverse colon?

A

at the hepatic flexure

34
Q

what type of organ is the transverse colon?

A

intraperitoneal organ

35
Q

where does the transverse colon extend from?

A

ascending colon at hepatic flexure to the descending colon at the splenic flexure

36
Q

relative to the hepatic flexure where is the splenic flexure?

A

higher up, due to big size of the liver

37
Q

what suspends the transverse colon?

A

by transverse mesocolon

38
Q

what can the transverse mesocolon be easily confused with in the lab?

A

with the greater omentum

39
Q

what type of organ is the descending colon?

A

retroperitoneal organ

40
Q

where does the descending colon extend from?

A

Extends down from the splenic flexure and distally will continue as the sigmoid colon

41
Q

what type of organ is the sigmoid colon?

A

intraperitoneal organ

42
Q

how is the sigmoid colon shaped?

A

Forms S shaped loop

43
Q

where does the sigmoid colon extend from?

A

ends at the sacrum and continues to the rectum

44
Q

what suspends the sigmoid colon?

A

fan-shaped sigmoid mesocolon

45
Q

what is the final portion of the colon?

A

rectum and anal canal

46
Q

how could the lumen of the colon be described as?

A

large

47
Q

what is teniae coli of the colon?

A

3 thickened binds of longitudinal muscles

48
Q

what does the teniae coli create?

A

folds onto itself such as ruching in dresses

49
Q

what is the function of the haustra?

A

Out-pockets to have fecal matter clumping together in order to better absorb H20 and Ions

50
Q

what are epiploic appendages?

A

Fatty tags enclosed by peritoneum attached in rows along teniae coli

51
Q

what is the function of the epiploic appendages?

A

Provide proprioception for the colon

52
Q

What A gives blood to the midgut?

A

superior mesenteric A

53
Q

what gives blood to the hind gut?

A

Inferior mesenteric A

54
Q

at what level can the SMA be identified?

A

L1

55
Q

at what level can the IMA be identified?

A

L3

56
Q

where does the SMV sit and where does the SMA sit?

A

vein sits on the right near IVC

artery sits on the left near aorta

57
Q

how does the SMA travel?

A

Comes off of the aorta and travels posterior to the D1 segment and the neck of the pancreas

58
Q

what is created by the jejunal and ileal branches of the SMA?

A

Creates the vascular arcades that go towards jejunum and ileum

59
Q

how do the ileal and jejunal branches travel? think of the drawing

A

travel on the left side of the loop of the SMA

60
Q

what are the main braches that comes from the right of the SMA?

A

inferior pancreaticoduodenal A (anterior and posterior)
ileocolic A
right colic A
middle colic A

61
Q

where does the ileocolic A travel?

A

• Towards the cecum and ileum also close to the appendix

62
Q

the appendicular A is a branch of what A?

A

ileocolic A

63
Q

where does the right colic A travel to?

A

ascending colon

64
Q

where does the middle colic A travel to?

A

to the transverse colon, it comes up and will curl around the hepatic flexure

65
Q

does the IMA have a partnering vein?

A

no

66
Q

what branches arise from the IMA?

A

left colic A
sigmoidal aa
superior rectal A

67
Q

where does the left colic A travel to?

A

to the descending colon

68
Q

what joins with the left colic A to form the marginal A?

A

the middle colic A

69
Q

what aa supply the sigmoid portion of the colon?

A

sigmoidal aa

70
Q

what gets blood from the superior rectal A?

A

rectum and upper anal canal

71
Q

what is the marginal A of drummond important for?

A

providing blood supply in cases of blocks

72
Q

what is known as the watershed area?

A

splenic flexure

73
Q

what is the watershed area?

A

area of dual blood supply