生理学复习资料：【名解】消化生理

1、1.Basic Electrical Rhythms (BER) a. a rhythmical fluctuation of gut smooth muscle resting potentials from -60 to -50mV b. initiated by interstitial cells of Cajal(ICC). c. doesnt cause smooth muscle contraction but spikes riding on the depolarization do!2.mucus-bicarbonate barriera. the mucus coveri

2、ng is derived from mucus secreted by surface epithelial cells and foveolar cells. This insoluble mucus forms a protective gel-like coating over the entire surface of the gastric mucosa. The mucus protects the gastric mucosa from autodigestion and functions as lubrication reducing the mechanical dama

3、ge to the mucosa.b. the bicarbonate ions are secreted by the surface epithelial cells. The bicarbonate ions act to neutralize harsh acids.3.receptive relaxationa. main form for stomach to contain foodb. reflective relaxation of the smooth muscle of the gastric wall when eatingc. increase the capacit

4、y of the stomach from 50mL to 1.5L and store the chime to prevent emptying so early4.segmentationa.in the large intestine and small intestine, while predominating in the latterb. segmentation contractions move chyme in both directions, which allows greater mixing with the secretions of the intestine

5、sc. segmentation involves contractions of the circular muscles in the GI tract 5.tonic contractiona. the common patterns of GI mobilityb. slow but consistent contraction of the smooth musclec. to increase the pressure within the stomach to help chemical digestion and gastric emptying(same function i

6、n the small intestine)d. to maintain the normal contour and position of the stomach5.brain-get peptide:Some kinds of peptides regarded as gastrointestinal hormones also exist in the CNS, and some nervous peptide of CNS also exist in the gastrointestinal tract. These peptides are called brain-gut pep

7、tide including gastrin, somatostatin, etc.6.ENSa. controlling the Gastrointestinal System. b. great influence in the digestive process. c. composed of myenteric plexus(movement of the GI) and submucosal plexus(secretion and regulation of blood flow)7.peristalsisa. rhythmic wave-like contractions tha

8、t move food through the GI tractb. coordinate movement of the circular and longitudinal smooth rinsic factor:a. a glycoprotein secreted by parietal cellb. necessary for the absorption of vitamin B12 later on in the small intestine9.gastrointestinal hormonea. secreted by APUD cells in the

9、GI tractb. regulating digestion, the synthesis and secretion of other hormones, trophic function and immune function in the GI tractc. some kinds can be seen in the CNS called brain-gut peptide10.gastric emptyinga. the process of chyme entering the duodenum from the stomachb. about 46h for the whole

10、 emptying processc. driven by the pressure difference between stomach and duodenum11. enterohepatic circulation of the biliary acid:a. the circulation of biliary acids from the liver to the bile, followed by entry into the small intestine, absorption by the enterocyte and transport back to the liver

11、b. to perform the emulsification to its maximum12. mixed micellea. the concentration of biliary acid reaches a certain degree in the water, it accumulates to form the micelle of which the hydrophobic surface is internal and the hydrophilic surface is externalb. fatty acid, monoglyceride and cholesterol must combine with the micelle to absorb by the small intestine epithelium蠕动冲:蠕动速度快，传播距离远的蠕动。可一次将食糜