Machinery of Digestion.-From the number and differently formed structures which constitute the digestive organs, it will be observed that the function is a very highly complex process.  If the food were thrown directly into the circulating fluid, it could not be used for the purpose of nutrition.  It requires for its transformation into blood, bone and muscle, a series of complex machinery, each part of which is specially designed for the particular part it plays in this wonderful and complicated process.

 

Use of Mouth and Teeth.- the mechanical part, which, although not shown in this chart, may be carefully studied in the chart giving the different views of the head, is performed by the mouth and teeth, and pulverized food is subject to the action of the saliva.  The lubricated morsel of food is now gathered into a ball and conveyed to the back of the mouth by the muscles of the cheek and tongue.  On its arrival here, the soft palate lifts upward and closes the posterior nasal openings; the epiglottis shuts down over the trachea or windpipe, forming a bridge over which the food passes, thus preventing it from falling into the respiratory tract.

For this section I don’t really know to anything extraordinary, and I’m just going to move on to the next sections from here as we do have some interesting segments coming up shortly.