Page 91 - My FlipBook

it is one of the acts of nutrition. It has been said that man
lives by dying. Not a bit of it. The formation of waste
products is just as much a function of life as nutrition is a
function of life ; it is a shedding out of that which has been
once used. In every contraction of a muscle some material
of that muscular tissue is given out as urea; the chemical
form is changed, not by a falling to pieces of the tissue, but
by an act of the life force, and it is given out in a definite
chemical compound, a molecular form that is entirely differ-
ent from those in which it existed as protoplasm. Instead of
the multitude of combining equivalents, it is reduced to a
comparatively few equivalents. The material used as proto-
plasm in protoplasm is shed off in a simpler form and the
changes are in the direction of the inorganic kingdom. Then,
again, in the lungs carbonic acid is formed, and these two
form the waste products of the higher animals and of pretty
much all of the animal kingdom. There are some variations,
particularly in the product of urea; uric acid in some ani-
mals, particularly in the birds and the reptiles, and hippuric
acid in some other animals, and so on ; so that they are not
all alike. The same is true with the amoeba ; the same is
true with the earth worm. These cannot live thoroughly

excluded from the air ; they cannot live unless they shed out
their waste products, though they seem to have no special
organs for this purpose. In the earth worm no particular
organ for the elimination of waste products can be found;
these waste products are eliminated, apparently, by the same
organs that perform the nutritive function. With the plants
it is the same. All of the higher plants have their particular
forms of waste products. These are not given out by special
organs and eliminated and thrown out of the plant. Many
of the plants store them almost entirely in the leaves and in
the bark ; some of the plants store them in the unused part
of the wood, that part which, in the processes of growth, has
become inactive. In this way they are thrown out of the
active functioning portions of the plant, and are as com-
pletely eliminated as if they were thrown out of the plant
entirely. Of course, our trees build great structures ; they
are large builders of material that is more or less permanent.
Now, think a moment. These plants form poisons—the
alkaloids, opium, strychnia, nicotin^ and all of these poisons

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