Anatomy stomach/Intestins 3 Flashcards
What is the Largest of the visceral organs and the center for metabolic regulation?
Liver
Liver has how many lobules?
What do Lobules look like?
100,000
Lobules are hexagon shaped
What structures are found in the liver histology?
Radial liver sinusoids empty into a central vein.
Portal triads (bile duct, arteriole, and venule) are found at each corner of the lobule.
Lack of basement membrane allows solutes, even large proteins to percolate around the hepatocytes
Kupffer cells, found in the sinusoids, are the macrophages of the liver
Liver secretes bile into what structure?
bile canaliculi which travels outward toward bile ductules in the triads
The liver has how many functions/products?
What are the most important functions of the liver?
The liver has more than 200 functions/products, including:
Metabolic regulation
Hematologic regulation
Bile production
What does Metabolic Regulation do?
Regulates composition of circulating blood by filtering blood from the GI tract (hepatic portal system)
Stabilizes blood glucose levels
Regulates lipid circulation: triglycerides, fatty acids and cholesterol
Removes excess amino acids from blood
Removes waste products, converts ammonia to urea
Removes toxins and drugs
Stores vitamins (ADEK) and minerals
What does Hematologic regulation do?
Receives a large portion of circulating blood, so it can effectively:
Phagocytose old/damaged RBCs
Present antigens to allow immune response
Synthesize plasma proteins like albumins
Remove circulating hormones
Remove antibodies
Removal/storage of toxins, esp. fat soluble forms
What is the purpose of bile production?
Bile salts break up lipid droplets to promote enzymatic breakdown, then promote absorption of lipids by the intestinal epithelium
What hormone is required to stimulate bile release into the duodenum?
What enzyme is this hormone stimulated by?
The hormone CCK is required to stimulate bile release into the duodenum
CCK production is stimulated by chyme entering the duodenum, esp. lipid rich chyme
What are the three parts of the large intestine with regional specialization?
cecum, colon, and rectum
What are the functions of the large intestine?
Prominent functions are to store digestive wastes and absorb water
What is the rectum?
Rectum – expandable storage site
What creates Haustra?
What does Haustrum do?
Contractions of the remaining longitudinal muscle layer, called the taeniae coli, results in pouch-like units called haustra
along the length of the large intestine.
Distension of one haustrum promotes contraction of the circular smooth muscle to push the contents into the next haustrum.
The large intestine has larger _____ than the small intestine
Lumen
The large intestine has thinner _____ than the small intestine
walls
