A treatise on physiology and hygiene for educational institutions and general readers .. . erment—that is, itinduces changes in the food simply byits presence, but does not itself undergochange. The acidity of the gastricjuice, which is due to lactic acid, is notaccidental; for we And that the pepsincannot act in an alkaline solution—that is, one which is not acid or quantity of gastric juice secreteddaily is very large, probably not lessthan three or four pints at each this fluid is at once used inthe digestion of the food, it is notlost; since it is soon re-absorbed b


A treatise on physiology and hygiene for educational institutions and general readers .. . erment—that is, itinduces changes in the food simply byits presence, but does not itself undergochange. The acidity of the gastricjuice, which is due to lactic acid, is notaccidental; for we And that the pepsincannot act in an alkaline solution—that is, one which is not acid or quantity of gastric juice secreteddaily is very large, probably not lessthan three or four pints at each this fluid is at once used inthe digestion of the food, it is notlost; since it is soon re-absorbed bythe stomach, together wTith those partsof the food which it has digested andholds in solution. 26. Movements of the StomachThe inner coating of the stomach isthe mucous membrane, which, as wehave seen, furnishes the gastric juice. Next to this coating lies 25. What is the office of the gastric juice ? Acidity of the gastric juice ? Quantity ofgastric juice used ? What becomes of it ? 26. Muscular coat of the stomach ? Expansion and contraction of its fibres ? Action ofthe fibres ?. Fig. 2 Alimentary Canal—includ-ing Gullet, Stomach, Large andSmall Intestines. 116 DIGESTION. another, called the muscular coat, composed of involuntary muscularfibres, some of which run circularly, and others in a longitudinaldirection. These expand to accomodate the food as it is introduced,and contract as it passes out. In addition, these fibres are in con-tinual motion while food remains in the stomach, and they act insuch manner that the contents are gently turned round from sideto side, or from one end of it to the other. 27. By these incessant movements of the stomach, called theperistaltic movements, the gastric juice comes in contact with allparts of the food. We are, however, not conscious that thesemovements take place, nor have we the power to control such portions of the food as are sufficiently digested approachthe pylorus, it expands to allow them to pass out, and it


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Keywords: ., bookcentury1800, bookdecade1, booksubjectphysiology, bookyear1884