Old & New Concepts About The Origin Of Life On Earth
A little later his creation, the man started to ponder over the philosophy of life. It seems that the story about the origin of life is as older as the existence of man itself. With his efforts, and in the light of his access to investigators, the man continued his efforts to find out the truth about life and its beginning. It is one of the traditional old problems and most of us who work in this field are motivated more by curiosity than by the desire to produce anything of immediate practical value. One may ask that perhaps man condemns the secrete about life, but it is not a true answer. It is merely an investigation which proves the nature of man that he likes to seek to find and not to yield.
We may ask whether the theory of spontaneous generation is proved true on the scientific grounds. We shall say perhaps not, Leevivenhock and Needham insisted on it to be the right one, but Spallanzani opposed it, for a long period there was a heated debate between Needham and Spallanzani. Moreover, it is also rejected since we develop an idea of “generation without parents”.
It is very difficult to imagine the spontaneous development of life (living matter) from a nonliving matter by itself.
In the middle of 19th century, Louis Pasteur in France and John Tyndall in England finally proved that even bacteria do not come into existence from non-living matter. All living creature from microbe’s to humans are generated by the activity of parents of their own species.
At about the same time Darwin’s theory of evolution began to displace the biblical theory of creation. According to the Darwin, all the varied forms of life with which we are familiar have evolved Lived on the earth long ago.
Since Darwin’s time the accumulated evidence in the favor how the theory of evolution has become overwhelming. Few biologist, however, doubts that the complicated living organisms have evolved from very simple ones in much the way that Darwin proposed. Recent discoveries made by geologists are also favoring this view of the origin of life. The earth is 4-5 billion years old. The oldest fossils of fairly large animals first appear in the rock laid down about 0.5 billion years ago, However, studies of older rocks, show that microorganisms were present on the earth much earlier than that, As one goes back through older and older rocks specimens that microorganism become simpler and simpler.
The oldest known organisms, found in the rock and are little more than 3 billion years old look like very simple modern bacteria.
This idea takes us to the main problems of the origin of life. When the idea takes us to the main problems of the origin of life, then so many questions come to raise in our mind.
Where did the first microorganisms come from?? There can be two answers.
(1)-It must have evolved on the surface of earth. (2)-It must have arrived here from some other inhabited planet. The second answer looks more fantasy than the truth.
Modern work on this chapter began with the new theory of Russian scientist Alexander Oparin. It is based on the principle of continuity, the gradual transformation of nonliving matter into albuminous compounds. As for the way this transformation took place what chemical reaction led some 4 billion years ago to the formation of organic molecules resulting in the emergence of living organisms, there is no single answer to these question.
208 Until recently the following assumption was considered, the most likely billions of years ago. The earth’s atmosphere contained along with Carbon dioxide some quantities of hydrogen, methane and ammonia, under the impact of electric discharge and ultraviolet sun rays, different organic compounds; took shape in the atmosphere.
Abundant rains carried these compounds to the world ocean, which covered the earth at the time. There they accumulated and in the ultimate end formed the basis for the emergence of the primary living system.
About 30 years later a young American science Stanley Miller put Spain’s theory to the text of experiment. He filled a large flask with a mixture of methane, ammonia, water and hydrogen a reducing atmosphere. Next, he passed an electric discharge for a week or two. After turning off the electric discharge, Miller went on to analyses the products he made. The results were very encouraging among the products, the several of amino acids were present which are considered as most essential biological molecules. In twenty years after the first experiments much work has been done, this work is referred as “Per biotic Chemistry”. The growing knowledge of Prey biotic chemistry has not made it possible to synthesize the essential amino acids and other building blocks of life.
Still, there is one idea that irritates have any similarity with those occurring in the space? Had the contents of the atmosphere actually been as assumed by the scientist? It also looked difficult to believe that the earth’s atmosphere could ever have contained such substantial quantities of ammonia and hydrogen. These conclusions compelled scientists to search for different sources, of the raw materials for the synthesis of organic compounds at the early stages of earth’s development. Upon studying this question the scientist of Russia advanced a hypothesis to the effect that most favorable conditions for the formation and accumulation of carbon compounds appeared during the eruption of submarine volcanoes. Why volcanoes??
Yes volcanic products contain ammonia, methane hydrogen and carbon monoxide and carbon dioxide and it is common knowledge that all these gases easily form the predecessors of compound organic molecules prussic acid and diverse aldehyde, emerging from volcanoes into the surrounding ocean these molecules could have laid the beginning for the synthesis of amino acids, bases of nucleic acid, surge and other, molecules, essentials these are important for biochemical synthesis.
This assumption is also supported by the fact, there are more submarine volcanoes than surface once. This is precisely why they played a major role in the evolution of organic compounds.
Further detailed combined study of space research and specialists of volcanology studied the composition of the ejected gases and thermal water in the areas of volcanic activity. It turned out that volcanoes were actual generators of organic compounds. For instance, the hydrogen cyanide the key compound for the synthesis of compounds of organic molecules was ejected from burning hot, fissures of volcanoes, Aldehyde and ammonia. Last but not the least, lucky two dramatic confirmations of the speculations of prebiotic chemistry have recently become available one.
Recently a meteorite fell in a desert region near the town of Murchison in the Australian. A large quantity of the 20 amino acids that occur in the protein was found in the meteorite.
This shown to contain large quantities of acids. Many of life were formed spontaneously without the intervention of already living organisms.
Second: – The D radio astronomers have provided the other new evidence they have examined a number of large clouds of dust and gases that are present in our galaxy. They found that a number of small organic molecules are present.
Although we combine all this knowledge obtained from various branches of sciences physical chemistry, biochemistry, prebiotic & meteorites studies, still we feel unsaturated in the field of knowledge.
“The origin of on earth” will it remain a riddle forever??
The coming period of tremendous scientific progress has to answer this question.