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COSMOLOGY : OLD AND NEW
the soul and hence we are quite justified in regarding the soul as a separate non-material substance.
Within the last few decades the scientists are convinced that it is possible to explain all processes of life in terms of the laws of physics and chemistry. According to them the two most essential requisites of life are growth and reproduction. As a result of growth, the body exhibits locomotion and in higher animals, mental activity. All living beings contain two or three classes of chemical substances, whose special properties enable living systems to exhibit the behaviour which we characterise as life. These substances belong to the category of high polymers whose molecules contain thousands of atoms and sometimes millions of them, arranged in repeated patterns. The protein which is one of the main constituents of all living matter belongs to this group. There are twenty protein units. They do specified jobs and produce required results. For instance, a protein called the haemoglobin (the chief constituent of blood) contains some iron atoms and serves the purpose of absorbing the oxygen from the air we breathe in and taking it to the various places in the body where the oxygen is required for maintaining the living process. There are thousands of different proteins inside any living organism and there is some sort of guiding force which exists in the cells of its tissues, which makes these proteins as required for doing their specialised duties. The guiding force is supplied by the two nucleic acids found inside the nucleius of the cells technically known as DNA and RNA.
In unicellular organisms such as the amoeba. The single cell at appropriate time when it is big enough it automatically divides into two similar parts and each part is a complete amoeba. On the other hand, in higher animals which also start from a single cell the cells which divide do not go apart, but stick together to give shape and form to the living being. So, what appears as growth in this case is really produced by the reproduction of the cells. The DNA produces the required proteins and duplicates itself.
In the field of artificial production of life the successful synthesis of a living cell was reported long ago and in 1968 the ‘American Reporter' announced the synthesis of biologically active living cell. A biologically active cell is that which grows by automatic multiplication. At present the great Indian Chemist Mr. Khurana is trying to manufacture a gene.