334 ANATOMY FOR NURSES [Chap. XVII 



because of the presence of sugar. When the quantity is diminished, 

 as in fevers, it is generally highly colored, because the amount of 

 solids present is large. Other causes of change of color are the 

 presence of abnormal substances, and large doses of certain drugs. 



Reaction. — The reaction of human urine is largely dependent 

 on the kind of food we eat. Many of the waste products that 

 result from a mixed diet are acid, hence the reaction of human urine 

 is usually acid. On a diet of carbohydrates the urine will be alka- 

 line, as it is with herbivorous animals. If human urine is allowed 

 to stand for any length of time, it will become alkaline, because 

 bacteria will decompose the protein constituents into ammonia 

 and other alkalies. In certain diseased conditions of the urinary 

 organs this same process takes place within the body. 



Specific gravity. — The specific gravity depends upon the 

 amount of solid waste matters present in the urine. In health, 

 it may vary from 1.010 to 1.030. When the solids are dissolved 

 in a large amount of water, the specific gravity will naturally be 

 lower than when, from a deficiency of water, the urine is more 

 concentrated. A high specific gravity denotes the presence of 

 abnormal constituents ; as, for instance, the specific gravity is not- 

 ably heightened by the presence of sugar in diabetes mellitus. 

 A low specific gravity generally denotes the presence of albumin, 

 or hysteria or mere polyuria. 



Quantity. — The average quantity of urine secreted in twenty- 

 four hours by a healthy adult is from forty to fifty ounces (1.19 

 to 1.48 litres). A child voids relatively more urine than an adult, 

 but absolutely it voids less. 



From 2-5 years, 16-24 ounces. 

 ' From 5-8 years, 24-32 ounces. 

 From 9-16 years, 32-40 ounces. 



The quantity of urine may be increased by (1) the ingestion of 

 a large amount of liquids, (2) the action of diuretics, (3) nervous- 

 ness, (4) certain diseases such as diabetes insipidus, diabetes 

 mellitus, and hysteria. 



The quantity of urine may be decreased by (1) the ingestion of 

 a small amount of liquids, (2) vomiting, (3) diarrhoea, (4) high 

 fever, (5) disease of the kidneys, and (6) the action of diapho- 

 retics, muscular activity, or any treatment that induces free per- 

 spiration. 



