GI Flashcards
What artery supplies the transverse colon?
Middle colic artery
What artery supplies the ascending colon?
Right colic artery
What arteries supply the illeum and jejunum?
Jejunal and ileal arteries, arterial arcases and vasa recta
What arteries supplies the illeum, cecum, appendix?
Ileocolic artery
What supplies the descending colon?
Left colic artery
What supplies the sigmoid colon?
Sigmoid artery
Rectum is supplied by:
Superior rectal artery
Wht are the portosystemic anastomoses for esophagael varices? and clinical significance?
left gastric and azygous vein
What are the portosystemic anastomoses for umbilicus and clinical significance?
paraumbilical and inferior epigastric
caput medusa
What are the portosystemic anastomoses for rectum and clinical significance?
superior rectal vein–middle and inferior rectal vein
hemorrhoids
Begins digestion of carbohydrates, particularly starches, by hydrolyzing α-1,4 bonds to form disaccharides. It is inactivated by the low pH of the stomach:
a- amylase or ptyallin
Begins digestion of lipids; breaks down triglycerides into fatty acids and monoglycerides. It is capable of continued digestion within the stomach. In contrast to pancreatic lipase, it can cleave fatty acids from all three
positions on a triglyceride:
lingual lipase
The composition of saliva:
high in bicarbonate and potassium
low in Na and cl
What happens at high flow rates of saliva?
Ductal cells decrease Na reabsorption and K secretion, however bicorbonate secretion increases.
In low flow rate states, saliva is ________ relative to plasma
Hypotonic; with low Na+ and Cl- and high K+
In the first step of the deglutition, what is the purpose of the soft palate?
to prevent reflux of into the nasal cavities
In the second step, what constricts and why?
Palatopharyngeal folds constrict to only allow allow properly masticated foods to pass
Third step of deglutition is?
closure of the epiglottis over the trachea
What happens to the Upper esophageal sphincter? (4th step)
It relaxes in <1 second and peristalsis wave moves bolus to pharynx to esophagus. During this phase breathing is inhibited
What controls esophagael phase?
Both swallowing and enteric nervous system.
What happens during esophagael phase?
Movement of the food to the stomach, the lower esophagael sphincters relaxes as a result of vagal stimulation (VIP)
What happens to UES after food passes?
It contracts to prevent reflux into pharynx
What occurs in vomitting reflex?
Reverse peristalsis
Stomach and pylorus relaxes
forced inspiration
LES relaxes
Forced expulsion
What is secreted in the body of the stomach and what are there functions?
Parietal cells- Secrete (H+) and IF- needed for B12 absorption
Chief cells- secrete pepsinogen (protein digestion)