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under certain conditions which nature has fixed. The germ cell--as has been established by the microscope--is the tiny cell which in the lowest living organisms as well as in man himself, forms the unit of physical development. Yet even this tiny cell is already a highly organized and perfected thing. It is composed of the most widely differing elements which, taken together, form the so-called protoplasm or cellular substance. And for all life established in nature the cell remains the constant and unchanging form element. It comprises the cell-protoplasm and a nucleus imbedded in it whose substance is known as the nucleoplasm. The nucleus is the more important of the two and, so to say, governs the life of the cell-protoplasm. The lower one-celled organisms in nature increase by division, just as do the individual cells of a more highly organized, many-celled order of living beings. And in all cases, though death or destruction of the cells is synonymous with the death or destruction of the living organism, the latter in most cases already has recreated itself by reproduction. We will not go into the very complicated details of the actual process of the growth and division of the protoplasmic cells. It is enough to say that in the case of living creatures provided with more complicated organisms, such as the higher plants, animals and man, the little cell units divide and grow as they do in the case of the lower organisms. The fact is one which shows the intimate inner relationship of all living beings. THE LADDER OF ORGANIC ASCENT As we mount the ascending ladder of plant and animal life the unit-cell of the lower organisms is replaced by a great number of individual cells, which have grown together to form a completed whole. In this complete whole the cells, in accordance with the specific purpose for which they are intended, all have a different form and a different chemical composition. Thus it is that in the case of the plants leaves, flowers, buds, bark, branches and stems are formed, and in that of animals skin, intestines, glands, blood, muscles, nerves, brain and the organs of sense. In spite of the complicated nature of numerous organisms we find that many of them still possess the power of reproducing themselves by division or a process of "budding." In the case of certain plants and animals, cell-groups grow together into a so-called "bud," which later detaches itself from
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