Notes on physiology / by Henry Ashby.

  • Henry Ashby
Date:
1889
Catalogue details

Licence: Public Domain Mark

Credit: Notes on physiology / by Henry Ashby. Source: Wellcome Collection.

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    Aloore^s test.—Boil with caustic potass ; if sugar is present the hquid will become first light yellow and afterwards brown. Fermentation test,—Add a small quantity of yeast, and leave in a warm place for 24 hours; a considerable quantity of carbonic acid will be evolved, which can be collected in a suitable apparatus. Alcohol will be present in the liquid. 2. Maltose, Ci_2H220i|, is the form of sugar which is mainly produced by the action of diastase on starch. It possesses more rotatory power ( + 150) over polarised light than dextrose ( + 58). Its re- ducing power over cupric oxide is less than that exercised by dextrose. Maltose is converted into dextrose under the influence of some of the intestinal ferments, and by boiling with dilute acids, but not by the action of malt diastase. 3. Milk Sugar or Lactose, Ci2H 220n, is found in milk. It differs from dextrose in being more insoluble in water, and not readily undergoing the alcoholic fermentation. It readily undergoes the lac- tic fermentation. It precipitates cuprous oxide from alkaline solutions in the same manner as dextrose. It is insoluble in alcohol. 4. Inosit, C^HigOg, occurs in small quantities in the spleen, liver, and brain, and appears in the urine in uraemia. It undergoes the lactic but not the alcoholic fermentation. 5. Glycogen, CeHjoOs, is found in considerable quantities in the livers of well-fed animals, in smaller quantities in the white corpuscles of the blood, placenta, and foetal tissues. It is an amorphous, white, tasteless powder, soluble in water, insoluble in alcohol. Its aqueous solution is opalescent. Preparation.—Kill a well-fed rabbit shortly after a meal, quickly remove the liver, and after cutting it in slices, throw it into boihng water without loss of
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