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.

    29/382 page 13
    Dextrin, time. After boiling for a short time (to prevent the ordinary post-mortem change which glycogen under- goes into grape sugar) pound the liver, boil again and filter. The filtrate contains the glycogen and certain albuminous substances which must be removed. The latter are precipated with potassio-mercuric iodide in the presence of hydrochloric acid. The glycogen is then precipitated by adding alcohol. Tests.—Dilute mineral acids (except nitric) con- vert it into grape sugar. Iodine gives a red colouration, which disappears on warming and reappears on cooling. (Starch gives blue with iodine, dextrin red, which disappears on warm- ing, and does not reappear on cooling.) 6. Dextrin, CeHioOr,.—Starch is converted into dextrin by the action of ferments, the dextrin formed being in turn converted into maltose if the action of the ferment is continuous. Dextrin is found in the alimentary canal and also in the blood. It becomes of a red colour on addition of iodine ; the colour disappears on warming and does not, as in the case of glycogen, reappear on cooling. IV. Hydro-Carbons, or Fats.—The principal fats present in the animal body are :— These neutral fats, when submitted to the action of superheated steam, or heated with lead oxide, com- bine with water, and form glycerine and a fatty acid. Palmitin Glycerine Palmitic acid C3H, (C16H3.O): H
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