no 



ELEMENTARY PHYSIOLOGY 



brane, while the undigested and indigestible portions pass onward 

 towards the rectum. 



As soon as the chyme is subjected to the influence of the bile 

 and pancreatic fluid, its appearance is changed, the emulsified fats 

 giving it the appearance of milk. The term chyle is applied to the 

 emulsified contents of the small intestine. 



After the chyle has passed through the whole length of the 

 small intestine, it enters the large intestine through an opening 

 which is guarded by two folds of the mucous membrane. These 

 folds project into the large tube, and so prevent the reflux of the 

 contents into the small intestine. Thus they form a valve between 

 the ileum and the ccecum, which is known as the ileo-caecal 

 valve. 



Digestion continues in the large intestine ; the dissolved por- 

 tions are gradually absorbed, leaving a residue which becomes 

 more and more solid. 



The time occupied by the food in passing through the intes- 

 tines varies considerably. Perhaps the average for the small intes- 

 tine is twelve hours ; and, for the large, from twenty-four to thirty 

 six hours. 



, Coats . 



Digestion . 



Mucous- 



Secretions 



LAEGE INTESTINE 



SUMMAEY. 



/ Serous a continuation of the peritoneum. 



v .- 1 f External longitudinal fibres. 

 Muscular | /nfernaf cir ? ular fibre i 



Areolar. 



Valvulse conniventes folds 01 

 membrane. 



i Tubular. 

 Glands | Globular. 

 < Lobulated. 

 ( Mucus. 



J A secretion resem- 

 bling the pancre- 

 \ atic fluid. 

 .Villi engaged in absorption. 



I Continued action of saliva and gastric 

 fluid. 

 BUe Emulsifies fats. 

 / Converts starch into 

 sugar. 

 Pancreatic fluid -j Dissolves nitrogenous 



foods. 

 V Emulsifies fats. 



j Digestion completed. 



t Fluid portions absorbed, leaving a solid residue, 



