Applied Physiology

of the blood just as they are. Seeds and husks and tough strings of flesh all pass the length of the intestine and are not changed.

=22. How food gets into the blood.=--By the time food is half way down the intestine it is mostly liquid and ready to become part of the blood. This liquid soaks through the sides of the intestine and into the blood tubes. At last the food reaches the end of the intestine. Most of its liquid has then soaked into the blood tubes and only some solid waste is left.

=23. Work of the liver.=--The food is now in the blood, but has not become a part of it. It is carried to the liver. There the liver changes the food to good blood, and then the blood hurries on and feeds the cells of the body. Spoiled food may be swallowed and taken into the blood with the good food. The liver takes out the poisons and sends them back again with the bile. The liver keeps us from getting poisoned.

Sometimes the stomach and intestine cannot digest the food. They canno