alive, but after we eat it the body makes
it alive. We do not know how it does it. When the body dies we cannot
put life into it again. There is life in each cell.

WHAT WE HAVE LEARNED

1. The body is made of five things: water, albumin, fat, sugar,
and minerals.

2. Water is mixed with all parts of the body.

3. Albumin makes the living part of each cell.

4. Fat is in pockets between the cells. It warms the cells and
keeps them from being hurt.

5. Sugar is made from starch. It warms the body.

6. The minerals in the body are salt, lime, iron, soda, and potash.

CHAPTER III

DIGESTION OF FOOD IN THE MOUTH

=11. Food of the cells.=--All the cells of the body work and wear out.
They must eat and keep growing. The food of the cells is the blood.
Water, albumin, fat, sugar, and minerals are in the blood. The cells
eat these things and grow. All food must be one or more of these five
things. Before they reach the blood, they must all be changed to a
liquid. A few cells of the body are set aside to do this work of
changing them. Changing food into blood is digestion.

=12. Cooking.=--Cooking begins digestion. It softens and dissolves
food. It makes food taste better. Most food is unfit for use until it
is cooked. Poor cooking often makes food still worse for use. Food
should always be soft and taste good after cooking. Softening food by
cooking saves the mouth and stomach a great deal of work. The good
taste of the food makes it pleasant for them to digest it. We must cut
our food into small pieces before we eat it. If we eat only a small
piece at a time we shall not eat too fast. If we cut our food fine we
can find any bones and other hard things, and can keep them from
getting inside the body.

=13. Chewing.=--Digestion goes on in the mouth. The mouth does three
things to food. _First_, it mixes and grinds it between the teeth.

_Second_, it pours water over the food through fine tubes. The water of
the mouth is called the saliva. The saliva makes the food a thin paste.

_Third_, the saliva changes some of the starch to sugar. Starch must
be all changed to sugar before it can feed the cells.

=14. Too fast eating.=--Some boys fill their mouths with food. Then
they cannot chew their food and cannot mix saliva with it. They
swallow their food whole, and then their stomachs have to grind it.
The saliva cannot mix with the food and so it is too dr