The Fairy-Land of Science

In the orange-pulp these cells contain only sweet juice, but in other parts of the orange-tree or any other plant they contain a sticky substance with little grains in it. This substance is called "protoplasm," or the first form of life, for it is alive and active, and under a microscope you may see in a living plant streams of the little grains moving about in the cells. Now we are prepared to explain how our plant grows. Imagine the tiny primrose plantlet to be made up of cells filled with active living protoplasm, which drinks in starch and other food from the seed-leaves. In this way each cell will grow too full for its skin, and then the protoplasm divides into two parts and builds up a wall between them, and so one cell becomes two. Each of these two cells again breaks up into two more, and so the plant grows larger and larger, till by the time it has used up all the food in the seed-leaves, it has sent roots covered with fine hairs downwards into the earth, and a shoot with beginnings of leaves up into the air. Sometimes the seed-leaves themselves come above the ground, as in the mustard-plant, and sometimes they are left empty behind, while the plantlet shoots through them. And now the plant can no longer afford to be idle and live on prepared food. It must work for itself. Until now it has been taking in the same kind of food that you and I do; for we too find many seeds very pleasant to eat and useful to nourish us. But now this store is exhausted. Upon what then is the plant to live? It is cleverer than we are in this, for while we cannot live unless we have food which has once been alive, plants can feed upon gases and water and mineral matter only. Think over the substances you can eat or drink, and you will find they are nearly all made of things which have been alive: meat, vegetables, bread, beer, wine, milk; all these are made from living matter, and though you do take in such things as water and salt, and even iron and phosphorus, these would be quite useless if you did not eat and drink prepared food which your body can work into living matter.