intestines and colon Flashcards
T/F: The Duodenum is a derivative of the foregut and the midgut
True
Large intestine divided into segment based on direction of movement: (list seg)
Cecum–> ascending colon –> transv colon –> desc colon –> sigmoid –. rectum
Transverse colon crosses from ____ to ____ quadrant
From upper right to upper left
Final part of the hindgut:
Rectum
Name/describe the 2 flexures of the colon:
Hepatic Flexure (right colic flexure, near liver)
Splenic Flexure (left colic flexure, near spleen)
What segments of the duodenum are located in the midgut?
3 and 4
Jejunum and Ileum progress from ____ to ____ quadrant
upper left to lower right quadrant of abdomen
location of: Midgut to Hindgut Transition
first 2/3 of transverse colon
Supplies entire midgut
–largest branch of abdominal aorta
–crosses over third segment of duodenum
Superior Mesenteric Artery
(Branches of SMA)
Supply jejunum and Ileum
–straight arteries (vasa recta) branch off anastomosing loops to supply intestine
Intestinal Arteries
(Branches of SMA)
Supplies:
DIstal ileum
Cecum
apppendix (via apendic art)
FIRST part of ascending colon
Ileocecal Artery
(Branches of SMA)
Supplies ascending colon
Right Colic Artery
(Branches of SMA..branches of Right Colic Artery)
–Supplies upper part of ascend colon
–supplies lower part, with anast connecting to ileocecal artery
–ascending branch
–descending branch
(Branches of SMA)
Supplies transverse colon (up to transition)
Middle Colic Artery
(Branches of Middle Colic Artery)
1) Supplies proximal transverse colon
2) Anastomoses with the inferior mesenteric artery
1) Right branch
2) left branch
–supplies part of pancreas and duodenum
–anastomoses with branch of Celiac Trunk!
–First branch of SMA
Inferior Pancreaticoduodenal Artery
Superior Mesenteric artery transitions to Inferior Mesenteric Artery at ____
2/3 of the transverse colon (Midgut to hind-gut transition)
_____ supply transitions from Vagus Nerve (Midgut) to Pelvic Splanchnic Nerves (Hindgut) at 2/3 of the transverse colon (Midgut to hind-gut transition)
Parasympathetic
Parasympathetic supply transitions from _____ (Midgut) to _____ (Hindgut) at 2/3 of the transverse colon (Midgut to hind-gut transition)
Vagus Nerve (mid) to Pelvic Splanchnic Nerves (hind)
Shortest and simplest part of GI Tract
hindgut
Anatomical Transitions of Hindgut
1) Tranverse colon
2) Descending Colon
3) Sigmoid Colon
4) Rectum
1) mesentery
2) secondarily retroperitoneal at splenic flexure
3) regains mesentary (at sigmoid mesocolon)
4) becomes secondarily retroperitoneal, attached to posterior pelvic wall
Primary Blood Supply for the hindgut:
Inferior Mesenteric Artery (runs down to left)
(branches of IMA)
supplies last part of transverse colon and the descending colon
–runs perpendicular to descending colon and divided into superior and inferior branches
left colic artery
The Left colic artery anastomoses with the middle colic artery at _______ near the mid/hind transition
at the Marginal Artery
(branches of IMA)
Supplies the sigmoid colon–located in the sigmoid mesocolon
Sigmoid Arteries
Sigmoid Arteries anastomose with the ___ above and the ____ below
left colic artery above; superior rectal artery below
Primary blood supply for the rectum
–Terminal branch of IMA
–retroperitoneal
Superior Rectal Artery
Superior rectal artery anastomoses with the ________
middle and inferior rectal arteries (which originate from the internal iliac artery in the pelvis)
Critical site for anastomoses between SMA and IMA
Marginal artery (located along mid/hind transition)
The mesenteric regions of the colon:
1) Transverse Mesocolon
2) Sigmoid Mesocolon
(have mesentery)
What are the secondarily retroperitoneal sections of the colon?
ascending colon, descending colon, and rectum
(attached to posterior abdominal wall)
Name the pericolic gutters:
1) Paracolic gutters–lateral to retroperitoneal sections of the colon
2) Paramesenteric gutters–around mesenteric regions
Channels formed along the reflections of the gut onto the parietal peritoneum or the root of the mesenteries
Pericolic gutters (important for passageway of abdominal infections)
