PRACTICAL URINE ANALYSIS AND PHYSIOLOGICAL CHEMISTRY. PHYSIOLOGICAL CHEMISTRY has to do with the examination of those processes which take place in the living organism, primarily as the result of the function of the organism itself, or secondarily by means of other or lower organisms which assist the higher one in its work. In the consideration of the vertebrate organism, these processes may be those which take place without outside help, such as respiration, the secretory function of the various glands and glandular structures, and also the investigation of those processes which take place by means of outside agencies. Into this class falls the digestive process to a large extent. Physiological chemistry also deals with the examination of food-stuffs, and the relation of these to nutrition and to the waste products formed in their use. The tissues of the body are also subject to examination in this respect, not only as to their composition, but also to the changes which may occur as a result of change in nutrition or in any other condition of environment. The first part of the exercises in physiological chemistry will be occupied with an examination of the stuffs which either enter into the composition of the animal body or are used by it as a means of nutrition or are excreted in the form of waste products. Following this will be an examination of physiological secretions of various kinds, and lastly an examination of some of the tissues of the body. Those substances which are met with in physiological chemistry may be roughly subdivided into inorganic and organic. In many cases these two classes of compounds are so closely in combination that it is impossible to separate them without destroying the compound itself. For this reason it is impossible to separate the inorganic part of physiological chemistry from the organic. In the classification of the organic compounds one may go in different directions, but as a rough subdivision one may take the classification into those which contain nitrogen and those which do not. To the latter class belong the carbohydrates and the fats, while in the former class fall all the protein substances of which the albumins are the chief members. Another member of this class is principal means of getting rid of This is urea, the diamid of car important as the waste nitrogen. bonic acid. |