xvi TABLE OF CONTENTS 



PAGE 



6. The Flow of Blood in the Capillaries . . . 219 



7. The Flow of Blood in the Veins 223 



A. Pressure and Velocity 223 



B. Aids to the Blood Flow in the Veins 224 



8. The Lesser Circulation and the Respiratory Variations of Blood Pressure 227 



A. The Pulmonary Circulation . . 227 



B. Respiratory Variations of Blood Pressure 229 



9. Vasoconstrictor Nerves 231 



10. Vasodilator Nerves 234 



11. Vasomotor Reflexes 235 



12. The Vasomotor Centers 237 



13. General Considerations on the Distribution of Blood in the Body . . 239 



A. Mechanical Influences 239 



B. The Influence of Vasomotor Nerves 240 



CHAPTER VII. Digestion 242 



First Section: The Digestive Fluids 242 



1. General Survey 242 



2. Saliva 245 



3. Gastric Juice 246 



A. The Acid of the Gastric Juice .247 



B. Pepsin 248 



C. Rennin 250 



D. Gastric Steapsin . 250 



4. Pancreatic Juice 251 



A. The Amylolytic Enzymes 251 



B. The Proteolytic Enzyme, Trypsin . . ... . . .252 



C. Lipolytic Enzyme, Steapsin 253 



5. Bile 253 



6. Intestinal Juice 255 



Second Section: Secretion of the Digestive Fluids 256 



1. General Survey 256 



2. The Salivary Glands 257 



A. Secretory Nerves 257 



B. Morphological Changes During Secretion 261 



3. The Glands of the Stomach 263 



A. Secretory Nerves 263 



B. The Gastric Glands 266 



C. Why Does the Stomach not Digest Itself? . . . . . .269 



4. Secretion of Pancreatic Juice 269 



A. Secretory Nerves 269 



B. Morphological Changes in the Pancreas 272 



5. The Liver and the Secretion of Bile . . . . . . . .272 



A. General Phenomena of Hepatic Secretion 272 



B. Dependence of the Secretion of Bile upon the Blood Supply . . 273 



C. The Discharge of Bile in Digestion 275 



6. The Glands of the Intestine 276 



A. Glands of the Small Intestine 276 



B. The Glands of the Large Intestine 277 



Third Section: Movements of the Alimentary Canal 278 



1. Mastication 278 



2. Sucking ... 279 



