GI (gastrointestinal tract) ---refers to Digestive System---tubular portion from esophagus---anus

*overtime all parts of DS are referred to as GI*

---everything that goes thru from esophagus to anus

----4 distinct layers-----

Oral cavity---bounded by lips and cheeks—contains tongue, teeth and salivary glands

-----starting place for ______________________________

---Lips---muscle with CT tissue skin---controlled by ____________________________------cheek----____________ muscle—flattens cheek to hold food over teeth

-----Tongue----holds food over teeth, primarily attached at root, under the tongue---strip of tissue attaching anterior portion----frenulum----à aids in ______________, ____________, and _____________ also is a sensory organ for taste)

--Motor controlled by______ cranial nerve---à __________________

Mechanical breakdown—mouth-à chew food-à big to little-à digestion of food---enzymes (amylase, breaks down 5% of ______________) ---split chemical bonds

----Uvula----most posterior portion of soft palate---rises up during deglutination (swallowing), blocks nasal cavity so food only goes down the esophagus

Pharynx--- consists of series of structures that make op throat---

-----Larynx---has set of _____________ pharyngeal constrictor muscles---take charge of food after chewed

Chew---mix with saliva---salivary amylase---back of throat---conscientious control stops

Digestive Process---voluntary (deglutination form to ball and push to back of throat) and involuntary phase (pharyngeal constrictor muscles ---take control ----1^st set constrict, 2^nd set, 3^rd set (controlled by___________ cranial nerve)

---Stomach- ________________________________________

Fundamental differences (compared to the tubular portion of the DS)

---3 layers of smooth muscle—

Small intestine----3 parts

1.

Duodenum==back to two muscle layers—inter circular and outer longitudinal separated by the auerbach plexus

Jejunum__________________________________________________________

*****THE LIVER DOESN’T PRODUCE DIGESTIVE ENZYMES********

________ Major lobes—________ and___________

----separated by the ______________________

Underside (inferior)

--minor lobes

****on the right major lobe****

_____________-stores bile

Porta-gate__________________________________

---place where hepatic portal vein enters the liver

--hepatic portal vein collects blood from all of the DS—enters liver

--branch of the hepatic artery (branch off the celiac trunk—branch off the aorta)

--hepatic ducts exit R & L one for each lobe come together and exit porta

Porta___________________________________________________________________________________________________________________________________________________________________________________________________________________

Inside liver—divided up into a whole bunch of lobules by CT septa

----hepatocytes

----hepatic cord_________________________________________________________

Hepatic portal vein____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Abdominal aorta_________________________________________________________

Superior side of liver____________________________________________________________________

Hepatic artery____________________________________________

Hepatic portal vein________________________________________

Drain liver______________________________________________________________

Central vein_____________________________________________________________

---Spaced all around lobule---portal triads---contain 3 components

Circulation of liver____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Pancreas________________________________________________________________________________________________________________________________________

Pancreatic duct-________________________________________________________________________________________________________________________________________________

LARGE intestine---

1^st portion –__________________

2^nd portion---colon

----4 parts----

Colon gives rise to rectum___________________________________________ 2 sphincter muscles

Mesentery__________________________________________________________

Ommentum_________________________________________________________

Chew-à mix with saliva-à salivary amylase-à back of throat-à conscientious control stops--à upper esophopharangeal sphincter relaxes( ring of smooth muscle)-à pharyngeal constrictor muscles constrict-à drop food into esophagus-à upper contracts---peristaltic( sequential contraction of muscualaris externa) moves from upper esophageal to lower esophageal-à lower esophageal( cardiac sphincter) -à opens food drops into stomach---à bolus of food into stomach—mix with digestive enzymes=semi fluid mixture called chyme---( semi fluid mixture of food and digestive enzymes)---à Stomach—lower esophageal (cardiac sphincter) and pyloric sphincter at bottom of stomach churn food with digestive enzymes----à sphincters stay closed-à stomach churns—>mix food-à chyme-à forced thru tonic pyloric sphincter( mostly closed)-à stomach contracts and squirts small amount of chyme into small intestine-----à

Carbohydrate breakdown---à starts in mouth—>salivary amylase—>small intestine---à pancreas will produce pancreatic amylase –>only capable of breaking down to disaccharide level—>border brush enzymes breakdown to final bonds, monosaccharide-à transported to intestinal mucosa--à as food is processed thru sm intestine—>segmental contractions--à peristaltic contractions-à illeocecal sphincter relaxes-à chyme-à into colon thru the illeocecal valveà colon is not interchangeable with large intestine, consists of more than just your colon

GOOD LUCK GUYS STUDY HARD AND YOU WILL ALL DO GREAT!!!!!!!!!!!!!!!