Gastrointenestinal and MSK Review Flashcards
Functions of the GI tract
Digestion, absorption excretion, endocrine
Mouth releases what proteins? What do they break down?
Salivary amylase - CHO/starch into maltose
Lingual lipase - fats into smaller fats
Gastric gland mucosal/neck cells secrete what?
Mucus
G cells produce gastrin
Function of gastrin?
Stimulate hydrochloric acid secretion from parietal cells
Stimulate gastric motility
Chief cells in the gastric glands produce what?
Pepsinogen
Parietal cells in the gastric glands secrete what? Functions?
Hydrochloric acid - activate pepsinogen, destroy bacteria
Intrinsic factor - absorb Vit B12
Mast cells in the gastric glands secrete?
Histamine
Food + gastric secretions =
Chyme
The presence of chyme in the small intestine causing S-cells in the duodenum to release? what does it do?
Secretin - stim pancreatic acinar cells to release bicarb and water, decrease gastric motility
Bicarbonate-rich mucus is secreted by what in the duodenum?
Brunner’s glands
Function of bicarbonate mucus?
Neutralize gastric acid in SI and make pH alkaline (protection)
Presence of fat in duodenum stimulates release of what from the I-cells of the duodenum? Function?
CCK - gallbladder contractin, sphincter of Oddi to relax, bile excretion into duodenum, stimulates pancreatic secretion of pancreatic amylase
Function of pancreatic amylase
Breakdown starch into maltose
Maltase breaks down maltose into?
2 molecules of glucose
Lactase breaks down glucose into?
Glucose and galactose
Sucrase breaks down sucrose into?
Glucose and fructose
Lactase, sucrase, maltase are found where in the enterocyte?
Brush border
Glucose is ACTIVELY transported into intestinal cells by?
Na+-G carrier
Digest fat is absorbed into central lacteals which drain where? Everything else goes where?
The Thoracic Duct
The liver
Fat breakdown products in the SI?
Fatty acids, glycerol
Starch, sucrose, lactose breakdown products in the SI?
Glucose, fructose, galactose
Protein breakdown products in the SI?
Amino acids
Exocrine cells in the pancreas are arranged into?
Acini
Exocrine cells of the pancreas secrete? which do?
Trypsinogen - activated to trypsin by enterokinase from enterocytes in the small intestine
Chymotryspin, carboxypolypeptidase, proelastase
Pancreatic amylase aids in digestion of starch to produce maltose
Lipase breaks down fat into fatty acids and glycerol
Endocrine cells in the pancreas are located where?
Islets of langerhans
Endocrine cell secretions from which cell type?
Glucagon - alpha cells
Insulin - beta cells
Somatostatin - delta cells
Where is most of the water absorbed in the GI tract?
Large intestine
Bacteria in the large intestine produce what Vitamin?
Vitamin K
Large intestine goblet cell secrete what? Why?
Mucus, aid in passage of feces
Fat soluble vitamins are?
ADEK
Water soluble vitamins enter enterocytes via 2o active transport using Na+-amino acid co-transporters except!!!
B12