simpler form than is necessary for dissolving them.(68)

*The Storage of Nutriment.*—For some time after the taking of a meal, food
materials are being absorbed more rapidly than they can be used by the
cells. Following this is an interval when the body is taking no food, but
during which the cells must be supplied with nourishment. It also happens
that the total amount of food absorbed during a long interval may be in
excess of the needs of the cells during that time; and it is always
possible, as in disease, that the quantity absorbed is not equal to that
consumed. To provide against emergencies, and to keep up a uniform supply
of food to the cells, it is necessary that the body store up nutrients in
excess of its needs.

*Methods of Storage.*—The general plan of storage varies with the
different nutrients as follows:

1. _The carbohydrates_ are stored in the form of _glycogen_. This, as
already stated (page 120), is a substance closely resembling starch. It is
stored in the cells of both the liver and the muscles, but mainly in the
liver (Fig. 78). It is a chief function of the liver to collect the excess
of dextrose from the blood passing through it, and to convert it into
glycogen, which it then stores within its cells. It does not, however,
separate all of the dextrose from the blood, a small amount being left for
supplying the immediate needs of the tissues. As this is used, the
glycogen in the liver is changed back to dextrose and, dissolving, again
finds its way into the blood. In this way, the amount of dextrose in the
blood is kept practically constant. The carbohydrates are stored also by
converting them into fat.

[Fig. 78]