288 



ANATOMY FOR NURSES 



[Chap. XV 



Carbohydrates. — All sugars and starches are grouped together 

 under the name of carbohydrates. They contain but three ele- 

 ments, carbon, hydrogen, and oxygen, the two latter in the pro- 

 portion to form water. The varieties of carbohydrates are as 

 follows : — 



Glucose or dextrose, found in fruits, es- 

 pecially the grape, and in the blood. 

 CeHnOc 

 Fructose or levulose, found with glucose 

 in fruits. C6H12O6. J 



r Sucrose or cane sugar. C12H22O11. 

 < Lactose or milk sugar. Ci2H220n. 

 I Maltose or malt sugar. C12H22OU. 



Simple or Mono 

 saccharids 



Complex or 

 Disaccharids 



Invert 

 sugai 



Sugars. — A study of the formulge of the complex sugars will 

 show that the composition is the same, but they are differently 

 named because they give different reactions. Before any of 

 the complex sugars can be utilized in the body they must first 

 be changed either into glucose, or into invert sugar, which consists 

 of a molecule each of glucose and fructose. One molecule of a 

 complex sugar plus one molecule of water will form one mole- 

 cule of glucose and fructose. 



Complex Sugar Water Glucose Fructose 



0^1^22011 + H2O = C6H12O6 . C(>Hi20c 



Invert Sugar. 



Polysaccharids < 



Starch — found in grain, tubers, roots, etc. (CeHioOs)/^ 



Cellulose — outside covering of starch 

 grains, and basis of all 

 woody fibres. (CeHioOs)?! 



Glycogen — form in which sugar is stored 



in liver. (C6nio05)n 



Dextrin — fomicfl from starch by par- 

 tial hydrolysis. (CeHioOs)/! 



Polysaccharids. — In all of these compounds the composition 

 of the molecule is supposed to be rather complex, although the 

 elements are present in each in the same relative proportion, 

 as shown in the formulae. The value of n, however, may be very 

 small or very large and is probably different for each polysaccha- 

 rid, which makes the actual composition of each member of the 



