objective 6 pt 3 Flashcards
major organ of digestion and absorption
6-7m long cadaver, 2-4m long during life
form pyloric sphincter to ileocecal valve; point at which joins large intestine
small intestine
what are the subdivisions of the small intestine?
duodenum
jejunum
ileum
25cm long; curves around head of pancreas
duodenum
2.5m long
jejunum
3.6m long; joins large intestine at ileocecal vale
ileum
what are the modifications of small intestine for absorption?
circular folds
villi
microvilli
folds of mucosa an submucosa that force chyme to slowly spiral through lumen, allowing more time for nutrient absorption
circular folds
fingerlike projections of mucosa with a core that contains dense capillary bed and lymphatic capillary called a lacteal for absorpotion
villi
give fuzzy appearance called the brush border that contains membrane-bound enzymes brush border enzymes, used for final carbohydrate and protein digesion
microvilli
what are the 5 major types of cells found in mucosal epithelium of villi and crypts?
enterocytes
goblet cells
enteroendocrine cells
panneth cells
stem cells
absorbing nutrients and electrolytes. also secrete intestinal juice in the villi
enderocytes
secrete mucous
goblet cells
source of enterogastrones
enteroendocrine
release antimicrobial agents and destroy certain bacteria
panneth cells
divide and differentiate to become other cell types
stem cells
