Concept of Abiogenesis and Biogenesis:
Many 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 man kind. These illusion 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, snacks and aquatic insects spontaneously developed from mud. This old belief that living beings can spontaneously develop from 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 Radi. Through performed some experiments he showed that all living organisms arise from their parents and negated the idea of abiogenesis.
The view that living beings can develop from other non living beings is called biogenesis. The following are a few of experiments which Redi performed and which led to the concept of biogenesis.
Experiment No. 1:
Some dead snakes were placed in a box. It noticed that flies gathered around the dead snakes. After three days maggots appeared in their bodies. About after eighteen days these maggots transformed into pupae. Some of these pupae were then transferred to separated glass containers covered with the sheet of paper. After eight days, a fly emerged from each pupa and all flies were similar to those which visited to the body of dead snakes. From this it was concluded that maggots were the offsprings of flies. The flies had laid egggs on the dead snacks. These eggs gave rise to maggots which formed pupae and ultimately flies emerged from them.Experiment No. 2:
In other experiment Radi took eight bottles. He put dead snacks in two pieces of meat in other bottle and dead fishes in other bottle. He kept four bottle open and four bottle covered. After a few days, maggots appeared in the open bottles only. No maggots appeared in the bottle kept covered. This showed that if the flies were prevented from entering the bottles, the maggots did not appeared.Some workers, however, criticized this experiment and said that the maggots failes to appeared in the covered bottles because air being so essential for abiogenesis could not enter these bottles. To test this, Radi performed another experiment.
Experiment No. 3:
Some pieces of meat were put in a bottle whose mouth was covered with the guaze. Sp we can say that, air could enter the bottle while flies remained out. Again no maggots appeared on the pieces 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 kf Abiogenesis is wrong.
Needham's Experiments:
In 1784, 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. These once again excited the believers pf Abiogenesis. For Example:Life from non life.
Pasture's experiment:
The arguement in the concept of biogenesis and abiogenesis continued upto the middle of nineteenth century, till Louis Pasture, a renowned French Scoentist proved with experiments, that abiogenesis could not occur in the present environment of earth.In 1864, Pasture performed his experiment, in front of commission formed of noticed biologists, to resolve this issue. He took flasks
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