Chapter 15 - Small Intestine Flashcards
Small bowel begins and ends where?
Duodenum to cecum
What is the average length of the small bowel in an adult?
5-6 meters
The common bile duct empties into the duodenum at the ___ __ ___?
Ampulla of Vater
After the duodenum, the proximal 2/5 of the small bowel is known as the ___?
Jejunum
After the jejunum you have the
Ileum
What type of cell is a villi?
Simple columnar epithelial cell
What feature does the villi and microvilli have to increase absorption?
Finger-like projections increases total surface area by 600 times
Where does the duodenum receive its arterial blood from?
Hepatic artery
Mucosa & submucosa layers arranged in a circular fold in the small bowel is called?
Plicae circulares
Apart from the duodenum, where does the rest of the small bowel derives its blood supply from?
Superior mesenteric artery
The entire small bowel blood supply drains through the ___ ___ vein.
Superior mesenteric vein
The duodenum is the primary site of __ and __ absorption.
Iron and calcium
The jejunum is the site of __, __ and __ absorption.
Fats, protein and carbohydrates
The ileum absorbs __ and __.
Vitermin B12 and bile acids
What are the 5 basic mechanism of absorption for the small bowel?
- Hydrolysis
- nonionic movement
- passive diffusion
- facilitated diffusion
- active transport
Within the small bowel, what are the three types of movements contributing to the mixing of chyme?
- Concentric & segmenting contractions
- Short, propulsive contractions or peristaltic waves (found predominantly in the first portion of duodenum and jejunum)
- Continuous shortening and lengthening of the villi
What affected area of the small intestine may lead to:
- Deficiency in iron and calcium
- Malabsorption of fats, proteins, and carbohydrates
- Malabsorption of vitermin B12 and bile acid
- Duodenum
- Jejunal
- Ileal
About 80% of all peptic ulcers occur where?
Duodenum
Peptic ulcer disease if left untreated can cause erosion of the mucosa and lead to what?
Hemorrhage, perforation and peritonitis
The mucosa is made of what cells?
simple epithelial cells
The submucosa is made up of
dense connective tissue containing arteries, venous and lymphatic plexuses.
The muscularis propria is made up of what muscles?
outer longitudinal and inner circumferential muscles
The serosa is composed of what cells?
mesothelial cells
The small, tubular glands known as the ‘crypts of Lieberkuhn’ is located where?
Between the villi
What is the primary function of the small bowel?
To absorb nutrients from the chyme 🥕
Peptic ulcers is caused by the bacteria _____
Helicobacter pylori (H. pylori)
Peptic ulcers if left untreated continues to erode the affected mucosa and can lead to ___, ____ & ____.
hemorrhage, perforation and peritonitis
Can you name a few parasitic diseases that affects the small bowel?
Giardiasis Coccidiosis Cryptosporidiosis Strongyloidiasis Ascariasis Diphyllobothriasis
Crohn’s disease can affect anywhere from the ___ to ____.
mouth to anus
Inflammatory Bowel Disease (IBD) is the term used to associate which two diseases?
Crohn’s and ulcerative colitis
What is the term volvulus?
An obstruction due to twisting of the GI tract.
Celiac disease is characterized by ____ & _____.
Poor food absorption and intolerance of gluten.
Treatment: Elimination of gluten from pt’s diet
What is short bowel syndrome?
A malabsorptive disorder as a result of decreased mucosal surface area, usually because of massive resection of the small bowel.
In lactose intolerance, there is a deficiency in the enzyme ___ which results in the malabsorption of the dissacharide lactose (sugar).
lactase
Lack of beta lipoproteins causes accumulation of fat and malabsorption resulting in increased stool fat. What is this condition called?
Abetalipoproteinmia
