Midgut GI Tract - Perfusion/Innervation Flashcards
The jejunum arises from?
the duodenum
What are the structures of the MidGut?
What makes them midgut structures?
Distal, second half of duodenum
Jejunum
Ileum
Ileocecal Valve
Cecum
Appendix
Ascending Colon
Hepatic Flexure
Transverse Colon (most of it)
They received their outline from the Superior Mesenteric Artery and its branches
The jejunum enters into?
Ileum
What is the function of the jejunum?
Absorption of nutrients
What perfuses the jejunum?
Superior mesenteric artery via intestinal arteries
What is the response of the jejunum when the vagus nerve is stimulated?
Parasympathetic. Increased peristalsis, absorption, and secretions in the small intestine.
What innervates the jejunum?
vagus nerve (parasympathetic);
thoracic sympathetic trunk T8-T10
(sympathetic),
sensation pathways: unconcious/reflex (vagus)
pain (sympathetic)
What is the response of the jejunum when the thoracic sympathetic trunk T8-T10 is stimulated?
Sympathetic. Decreased peristalsis, absorption, and secretions.
What nerves transmit pain sensations from the jejunum?
thoracic sympathetic trunk T8-T10 (sympathetic),
The midgut gets its blood supply from?
Superior Mesenteric Artery and its branches
Ileum arises from?
Jejunum
Ileum drains/emptys into?
Cecum through the ileocecal valve
Function of the Ileum
Absorption of nutrients
Blood supply of the Ileum
Superior mesenteric artery via intestinal arteries, Ileocolic artery
Innervation of the Ileum
vagus nerve (parasympathetic);
thoracic sympathetic trunk T8-T10 (sympathetic),
sensation pathways: unconcious/reflex (vagus) pain (sympathetic)
What occurs at the Ileum when the vagus nerve is stimulated?
Parasympathetic Activation.
Increased Motility/Peristalsis, Absorption, and Secretions
What occurs at the Ileum when the thoracic sympathetic chain T8-T10 nerves are activated?
Sympathetic Activation.
Decreased motility/peristalsis, absorption, and secretions.
What is the Ileocecal Valve
muscular valve at junction of ileum and cecum
Function of the Ileocecal Valve
Regulates passage of digesta from ileum to cecum (between small and large intestines)
Blood supply of Ileocecal Valve
Superior mesenteric artery via intestinal arteries, Ileocolic artery
Innervation of Ileocecal Valve
vagus nerve (parasympathetic);
thoracic sympathetic trunk T8-T10 (sympathetic),
sensation pathways: unconcious/reflex (vagus) pain (sympathetic)
The cecum arises from?
Ileum
The cecum drains/emptys into?
Ascending Colon
Function of the cecum
Absorption of water, concentration of feces
Blood supply of the cecum
Superior mesenteric artery via ileocolic artery
Innervation of the cecum
vagus nerve (parasympathetic);
thoracic sympathetic trunk ~T10 (sympathetic), sensation pathways: unconcious/reflex (vagus) pain (sympathetic)
What occurs in the large intestine when the thoracic sympathetic trunk is stimulated?
Sympathetic Activation
Decreased peristalsis, absorption, and secretions.
Liquid stool :( anxious diarrhea
What occurs in the large intestine when the vagus nerve is stimulated?
Increased motility, absorption, and secretion. Too much absorption can lead to constipation.
the appendix arises from?
Cecum
Function of appendix
No major function-hypothesized minor immune or gut microbiota function
the Ascending Colon arises from?
Cecum
the ascending colon drains into?
transverse colon
blood supply of the ascending colon
Superior mesenteric artery via right colic artery
Function of the ascending colon
Absorption of water, concentration of feces
Innvervation of the Ascending Colon
vagus nerve (parasympathetic);
thoracic sympathetic trunk T10-T12 (sympathetic),
sensation pathways: unconcious/reflex (vagus) pain (sympathetic)
Function of Taeniae coli
Band of connective tissue for attachment of muscle of large intestine
What is the Haustra
Sacculations of the large intestine giving distinct “segmented” appearance
What is the hepatic flexure
Midgut, junction between ascending and transverse colon on right side near liver
The transverse colon arises from?
Ascending Colon
Transverse Colon drains into?
Descending Colon
Function of transverse colon?
Absorption of water, concentration of feces
Blood supply of the transverse colon?
Superior mesenteric artery via middle colic artery
Innervation of Transverse Colon
vagus nerve (parasympathetic);
thoracic sympathetic trunk T10-T12 (sympathetic)
sensation pathways: unconcious/reflex (vagus) pain (sympathetic)
What attaches the transverse colon to the stomach
gastrocolic ligament
What is the splenic flexure
Junction between transverse and descending colon on left side near liver (junction of midgut and hindgut)
