The Digestive System


Categories: WHY WE HAVE A STOMACH
Sources: A Handbook Of Health

How the Food Reaches the Stomach. Our body, then, has an opening,

which we call the mouth, through which our food-fuel can be taken in.

A straight delivery tube, called the gullet, or esophagus, runs down

from the mouth to a bag, or pouch, called the stomach, in which the

food is stored until it can be used to give energy to the body, just as

the gasoline is stored in the automobile tank until it can be burned.



The mouth opening is furnished with lips to open and close it and

assist in picking up our food and in sucking up our drink; and, as much

of our food is in solid form, and as the stomach can take care only of

fluid and pulpy materials, nature has provided a mill in the mouth in

the form of two arches, of semicircles, of teeth, which grind against

each other and crush the food into a pulp.






In this diagram the entire alimentary canal is shown enlarged, and the

small intestine greatly shortened, in order to show distinctly the

course of the food in the process of digestion.]



In the bottom or floor of the mouth, there has grown up a movable bundle

of muscles, called the tongue, which acts as a sort of waiter, handing

the food about the mouth, pushing it between the teeth, licking it out

of the pouches of the cheeks to bring it back into the teeth-mill again,

and finally, after it has been reduced to a pulp, gathering it up into a

little ball, or bolus, and shooting it back down the throat, through

the gullet, into the stomach.



The Intestines. When the food has been sufficiently melted and

partially digested in the stomach, it is pushed on into a long tube

called the intestine, or bowel. During its passage through this part

of the food tube, it is taken up into the veins, and carried to the

heart. From here it is pumped all over the body to feed and nourish the

millions of little cells of which the body is built. This bowel tube, or

intestine, which, on account of its length, is arranged in coils,

finally delivers the undigested remains of the food into a somewhat

larger tube called the large intestine, in the lower and back part of

the body, where its remaining moisture is sucked out of it, and its

solid waste material passed out of the body through the rectum in the

form of the feces.





More

;