1.8
ORIGIN OF LIFE
1.8.1 Islamic view about the
Origin of life:
The Holy Quran throws adequate light on the origin of life. The most important fact in the teachings of Quran is that Allah is the ultimate creator of every thing. Living and non-living are both created by Him. There are several verses of Quran in this regard. A few are quoted below:
"He is the Creator of the heavens and the earth".
(Surah Al'Ana'm, Ayah 102}
"That is Allah your Lord. There is no god but Him, the Creator of all things. Therefore, serve Him. He is the Guardian of all things".
(Surah Al-Ana'm, Ayah 103)
The preceding verse explains that all living beings including insects and snakes (which crawl), monkeys and grazers (four legged creatures) and birds and humans (two legged creatures) were created ultimately from water. It is stated:
"We did create man from an essence of clay".
(Surah Al-mominoon, Ayah 12)
"He (Allah) who created all things in the best way. He first created man from clay, then bred his offspring from a drop of paltry fluid. He then moulded him and breathed into him of His spirit. He gave your eyes and ears, and hearts: yet you are seldom thankful".
(Surah Al-Sajda, Ayah 7-9}
Once the life had been created, Allah implemented the process of reproduction for the continuity of races of animals. The various stages of reproduction have been described in Holy Quran in following way.
"Then fashioned we the drop a clot, then fashioned we the clot a little lump, then fashioned we the little lump bones, then clothed the bones with flesh".
(Surah Al-mominoon, Ayah 14)
"Hath there come upon man (every) any period of time in which he was a thing unremembered?"
(Surah Al-Dahar, Ayah 1)
A close study of above sermons reveals that all animals had common origin but they gradually underwent changes afterwards and became different from each other i.e. some developed crawling, some started walking on two legs and some other had four. It seemed that animals of today are advanced forms of the past animals who achieved this form after passing through many changes.
1.8.2 Concepts of Abiogenesis and Biogenesis:
Man had believed since ancient times that living organisms (both plants and animals) arise from clay, earth and other non-living matter not from pre-existing parents of their own kind. This was based on such observations as growth of fungus on pieces of bread and the appearance of maggots on dead bodies of animals. Aristotle believed that fishes, frogs and aquatic insects spontaneously developed from mud. This old belief that living beings can spontaneously develop from the non-living is termed as abiogenesis.
The idea of production of living from the non-living was experimentally analyzed. The pioneer in such experiments was an Italian scientist named Redi. Through several experiments he showed that all living organisms arise from their parents and negated the idea of abiogenesis.
The view that living beings can develop only from other living being is called biogenesis. The following are a few of the experiments which Redi performed and which led to the concept of biogenesis.
Experiment No.1
Some dead snakes were placed in a box. It was noticed that flies gathered around the dead snakes. After three days maggots appeared in their bodies. After about eighteen days these maggots transformed into pupae. Some of these pupae were then transferred to separated glass containers covered with a sheet of paper. After eight days, a fly emerged from each pupa and all flies were similar to those which visited the body of the dead snakes. From this it was concluded that maggots were the offspring’s of flies. The flies had laid eggs on the dead snakes. These eggs gave rise to maggots which formed pupae and ultimately flies emerged from them.
Experiment No.2
In another experiment Redi took eight bottles. He put dead snakes in two; pieces of meat in other bottle and dead fishes in other bottle. He kept four bottles open and four covered. After a few days, maggots appeared in the open bottles only. No maggots appeared in the bottles kept covered. This showed that if the flies were prevented from entering the bottles, the maggots did not appear.
Some workers, however, criticized this experiment and said that the maggots failed to appear in the covered bottles because air being so essential for abiogenesis could not enter these bottles. To test this, Redi performed another experiment.
Experiment No.3
Some pieces of meat were put in a bottle whose mouth was covered with a gauze. Thus, air could enter the bottle while flies remained out. Again no maggots appeared on the piece of meat, even after many days inspite of the fact that entry of air was possible.
These experiments provide evidence supporting the idea that only living beings give rise to living beings. Thus, the concept of Biogenesis is correct and that of Abiogenesis is wrong.
Needham's experiment:
In 1748, an English Scientist Needham, boiled meat in water, poured this gravy in bottles and closed their mouth with cork. After a few days many micro-organisms were produced in these covered bottles. This once again excited the believers of Abiogenesis i.e. life from non-life (Fig: 1.3).
Pasture's experiment:
The argument on the issue of biogenesis and abiogenesis continued up to the middle of nineteenth century, till Louis Pasture, a renowned French scientist proved with experiments, that abiogenesis could not occur in the present environment of earth.
In 1864, Pasture performed his experiment, in front of the commission formed of noted biologists, to resolve this issue. He took flasks which had long curved S-shaped necks (Fig. 1.4). He added fermentable infusion (yeast + sugar + water) in bottles and left their mouth open.
The yeast infusions were boiled in the flasks and let steam released out of the neck of each flask. Then flasks were allowed to cool. No life was produced even after the lapse of several days; because micro-organisms entering along with incoming air got stuck up in on the curved walls of the glass neck. To prove this he broke up the curved necks, so that now contaminated air could reach directly to the infusion. It was observed that micro-organisms were produced within 48 hours. This proved that if care was taken and no micro-organisms or their spores were allowed to reach the infusion, no life could be produced. He rejected spontaneous generation. Commission decided in favour of bio-genesis.
1.8.3 Concept of chemical and organic evolutional
The modern view of origin of life stresses upon the idea of chemical evolution and ties its origin to the history of the earth and the primitive atmosphere.
How did it happen and what evidence supports this idea?
In the beginning, the universe was an intensely hot point where matter and energy were indistinguishable. About 15 billion year ago, there was a Big Bang (huge explosion). The universe started expanding and the temperature dropped drastically. In time, about 4.6 billion years ago our earth and other planets appeared as part of the solar system. The Primitive atmosphere of the earth was rich in Hydrogen. Soon gases from the very hot and liquid core of the earth added more elements to this atmosphere. It is believed that the earth's atmosphere at this stage consisted carbon monoxide, carbon dioxide, Hydrogen, Nitrogen, water vapours and was exposed to intense radiation and electric spark. It hardly had any free oxygen. With the passage of time, the atmospheric temperature gradually dropped. This allowed condensation and heavy rains which caused formation of oceans. Thunder and lightning sparks together with ultraviolet radiation caused reactions of the atmospheric gases. This led to formation of simple organic molecules. These molecules I came down with rain and accumulated in the oceans, lakes, rivers and the soil over a very long period of time. These molecules had enough chances to interact in this environment and produce amino acids and proteins which are the building blocks of life. This sequence of chemical evolution was demonstrated in the middle of the 20th century by some clever laboratory experiments. Scientists were able to produce amino acids and simple sugars from a mixture of methane, ammonia, hydrogen and water by exposing it to electric sparks. More recent experiments using electric sparks in laboratory chambers have successfully produced not only amino acids and sugar but also the basic ingredients of fatty substances and DNA, all of which are the constituents of life.
Life originated on earth more than 3.5 billion years ago. We do not know how life formed, although the evidence is consistent with the hypothesis that it evolved spontaneously from chemicals. There is considerable discussion among biologists about what the early stages of such an evolutionary process might have been like.
What was the first life form like? The first life form, perhaps, was a sphere of naked protein or RNA and was capable of making its copies (reproduction). At some stage, a membrane assembled around the sphere giving rise to the first cell. There is now general agreement that this first life form respired anaerobically because the earth's atmosphere lacked free oxygen; it reproduced asexually. Our present day knowledge of viruses, bacteria and how DNA makes its copies provide enough hints in support of the above view. The first living organism may have been like viruses.
The next step in this story was appearance of an autotrophic way of life, that is, an organism capable of photosynthesis, adding free oxygen into the atmosphere. This availability of free oxygen opened the way for an explosion of a variety of organisms in times to come. Further improvement became possible as some of the organisms achieved the capability, to reproduce sexually.
For at least the first 2 billion years of life on earth, all organisms were bacteria. About 1.5 billion years ago, the first eukaryotes appeared.
The story of origin of life highlights change in matter. First inorganic molecules interacted in a way that organic molecules came into existence. The latter formed aggregates capable of making their copies and existed as naked spheres of protein or nucleic acids (RNA or DNA). Ultimately there arose the first cell a unit with a membrane. This tells us that life eventually arose by a slow process of chemical changes or organic evolution. The basic underlying concept in this process is that over a period of time (a very long period) one form gave rise to another. The idea of organic evolution was supported by scientist like Lamarck and Charles Darwin. They argued that new forms of life must have arisen from older ones through variations and that it was something in the process of heredity which was responsible for variations.
The Holy Quran throws adequate light on the origin of life. The most important fact in the teachings of Quran is that Allah is the ultimate creator of every thing. Living and non-living are both created by Him. There are several verses of Quran in this regard. A few are quoted below:
"He is the Creator of the heavens and the earth".
(Surah Al'Ana'm, Ayah 102}
"That is Allah your Lord. There is no god but Him, the Creator of all things. Therefore, serve Him. He is the Guardian of all things".
(Surah Al-Ana'm, Ayah 103)
The preceding verse explains that all living beings including insects and snakes (which crawl), monkeys and grazers (four legged creatures) and birds and humans (two legged creatures) were created ultimately from water. It is stated:
"We did create man from an essence of clay".
(Surah Al-mominoon, Ayah 12)
"He (Allah) who created all things in the best way. He first created man from clay, then bred his offspring from a drop of paltry fluid. He then moulded him and breathed into him of His spirit. He gave your eyes and ears, and hearts: yet you are seldom thankful".
(Surah Al-Sajda, Ayah 7-9}
Once the life had been created, Allah implemented the process of reproduction for the continuity of races of animals. The various stages of reproduction have been described in Holy Quran in following way.
"Then fashioned we the drop a clot, then fashioned we the clot a little lump, then fashioned we the little lump bones, then clothed the bones with flesh".
(Surah Al-mominoon, Ayah 14)
"Hath there come upon man (every) any period of time in which he was a thing unremembered?"
(Surah Al-Dahar, Ayah 1)
A close study of above sermons reveals that all animals had common origin but they gradually underwent changes afterwards and became different from each other i.e. some developed crawling, some started walking on two legs and some other had four. It seemed that animals of today are advanced forms of the past animals who achieved this form after passing through many changes.
1.8.2 Concepts of Abiogenesis and Biogenesis:
Man had believed since ancient times that living organisms (both plants and animals) arise from clay, earth and other non-living matter not from pre-existing parents of their own kind. This was based on such observations as growth of fungus on pieces of bread and the appearance of maggots on dead bodies of animals. Aristotle believed that fishes, frogs and aquatic insects spontaneously developed from mud. This old belief that living beings can spontaneously develop from the non-living is termed as abiogenesis.
The idea of production of living from the non-living was experimentally analyzed. The pioneer in such experiments was an Italian scientist named Redi. Through several experiments he showed that all living organisms arise from their parents and negated the idea of abiogenesis.
The view that living beings can develop only from other living being is called biogenesis. The following are a few of the experiments which Redi performed and which led to the concept of biogenesis.
Experiment No.1
Some dead snakes were placed in a box. It was noticed that flies gathered around the dead snakes. After three days maggots appeared in their bodies. After about eighteen days these maggots transformed into pupae. Some of these pupae were then transferred to separated glass containers covered with a sheet of paper. After eight days, a fly emerged from each pupa and all flies were similar to those which visited the body of the dead snakes. From this it was concluded that maggots were the offspring’s of flies. The flies had laid eggs on the dead snakes. These eggs gave rise to maggots which formed pupae and ultimately flies emerged from them.
Experiment No.2
In another experiment Redi took eight bottles. He put dead snakes in two; pieces of meat in other bottle and dead fishes in other bottle. He kept four bottles open and four covered. After a few days, maggots appeared in the open bottles only. No maggots appeared in the bottles kept covered. This showed that if the flies were prevented from entering the bottles, the maggots did not appear.
Some workers, however, criticized this experiment and said that the maggots failed to appear in the covered bottles because air being so essential for abiogenesis could not enter these bottles. To test this, Redi performed another experiment.
Experiment No.3
Some pieces of meat were put in a bottle whose mouth was covered with a gauze. Thus, air could enter the bottle while flies remained out. Again no maggots appeared on the piece of meat, even after many days inspite of the fact that entry of air was possible.
These experiments provide evidence supporting the idea that only living beings give rise to living beings. Thus, the concept of Biogenesis is correct and that of Abiogenesis is wrong.
Needham's experiment:
In 1748, an English Scientist Needham, boiled meat in water, poured this gravy in bottles and closed their mouth with cork. After a few days many micro-organisms were produced in these covered bottles. This once again excited the believers of Abiogenesis i.e. life from non-life (Fig: 1.3).
Pasture's experiment:
The argument on the issue of biogenesis and abiogenesis continued up to the middle of nineteenth century, till Louis Pasture, a renowned French scientist proved with experiments, that abiogenesis could not occur in the present environment of earth.
In 1864, Pasture performed his experiment, in front of the commission formed of noted biologists, to resolve this issue. He took flasks which had long curved S-shaped necks (Fig. 1.4). He added fermentable infusion (yeast + sugar + water) in bottles and left their mouth open.
The yeast infusions were boiled in the flasks and let steam released out of the neck of each flask. Then flasks were allowed to cool. No life was produced even after the lapse of several days; because micro-organisms entering along with incoming air got stuck up in on the curved walls of the glass neck. To prove this he broke up the curved necks, so that now contaminated air could reach directly to the infusion. It was observed that micro-organisms were produced within 48 hours. This proved that if care was taken and no micro-organisms or their spores were allowed to reach the infusion, no life could be produced. He rejected spontaneous generation. Commission decided in favour of bio-genesis.
1.8.3 Concept of chemical and organic evolutional
The modern view of origin of life stresses upon the idea of chemical evolution and ties its origin to the history of the earth and the primitive atmosphere.
How did it happen and what evidence supports this idea?
In the beginning, the universe was an intensely hot point where matter and energy were indistinguishable. About 15 billion year ago, there was a Big Bang (huge explosion). The universe started expanding and the temperature dropped drastically. In time, about 4.6 billion years ago our earth and other planets appeared as part of the solar system. The Primitive atmosphere of the earth was rich in Hydrogen. Soon gases from the very hot and liquid core of the earth added more elements to this atmosphere. It is believed that the earth's atmosphere at this stage consisted carbon monoxide, carbon dioxide, Hydrogen, Nitrogen, water vapours and was exposed to intense radiation and electric spark. It hardly had any free oxygen. With the passage of time, the atmospheric temperature gradually dropped. This allowed condensation and heavy rains which caused formation of oceans. Thunder and lightning sparks together with ultraviolet radiation caused reactions of the atmospheric gases. This led to formation of simple organic molecules. These molecules I came down with rain and accumulated in the oceans, lakes, rivers and the soil over a very long period of time. These molecules had enough chances to interact in this environment and produce amino acids and proteins which are the building blocks of life. This sequence of chemical evolution was demonstrated in the middle of the 20th century by some clever laboratory experiments. Scientists were able to produce amino acids and simple sugars from a mixture of methane, ammonia, hydrogen and water by exposing it to electric sparks. More recent experiments using electric sparks in laboratory chambers have successfully produced not only amino acids and sugar but also the basic ingredients of fatty substances and DNA, all of which are the constituents of life.
Life originated on earth more than 3.5 billion years ago. We do not know how life formed, although the evidence is consistent with the hypothesis that it evolved spontaneously from chemicals. There is considerable discussion among biologists about what the early stages of such an evolutionary process might have been like.
What was the first life form like? The first life form, perhaps, was a sphere of naked protein or RNA and was capable of making its copies (reproduction). At some stage, a membrane assembled around the sphere giving rise to the first cell. There is now general agreement that this first life form respired anaerobically because the earth's atmosphere lacked free oxygen; it reproduced asexually. Our present day knowledge of viruses, bacteria and how DNA makes its copies provide enough hints in support of the above view. The first living organism may have been like viruses.
The next step in this story was appearance of an autotrophic way of life, that is, an organism capable of photosynthesis, adding free oxygen into the atmosphere. This availability of free oxygen opened the way for an explosion of a variety of organisms in times to come. Further improvement became possible as some of the organisms achieved the capability, to reproduce sexually.
For at least the first 2 billion years of life on earth, all organisms were bacteria. About 1.5 billion years ago, the first eukaryotes appeared.
The story of origin of life highlights change in matter. First inorganic molecules interacted in a way that organic molecules came into existence. The latter formed aggregates capable of making their copies and existed as naked spheres of protein or nucleic acids (RNA or DNA). Ultimately there arose the first cell a unit with a membrane. This tells us that life eventually arose by a slow process of chemical changes or organic evolution. The basic underlying concept in this process is that over a period of time (a very long period) one form gave rise to another. The idea of organic evolution was supported by scientist like Lamarck and Charles Darwin. They argued that new forms of life must have arisen from older ones through variations and that it was something in the process of heredity which was responsible for variations.
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