The Disproval Of Spontaneous Generation Essays - Origin Of Life

The Disproval Of Spontaneous Generation From the beginning of time it was believed that living things could come from nonliving things. This process was known as spontaneous generation. However, in the middle of the 17th century and then through the next 100 years, this idea was disproved by three important experiments. We now know that a nonliving object or group of objects can not turn into a living organism. Spontaneous generation is impossible in the atmosphere that we have today. In the early 1600s, people believed that living organisms could evolve from nonliving organisms. They proved this by saying that if a piece of meat was left out uncovered, that maggots would appear in a few days. These worms did not come from anything that they could see, so they assumed they came from the nonliving meat. In 1668, a man named Redi designed and completed an experiment that showed how this was not true. He took two pieces of raw meat, and left them out. He covered one so that nothing could get in, and left the other one open. The open one grew maggots, and the covered one did not, proving that the dead meat did not produce the worms as they had previously thought. In the 1700s a man named Spallanzani proved Redis idea to a further extent. He noticed microbial growth on boiled pond water after being exposed to the air. To prove that this growth came from something living in the air, and not from the nonliving water, he designed an experiment. He boiled pond water to kill all the microbial growths. He then poured that water into two separate test tubes. He sealed one so that no air could get in, and left one open to the air. The one that was left open slowly became more and more cloudy with microbial growths. The sealed tube stayed as clear as it had been when it was boiled. This experiment proved that the growths could not come from nonliving organisms, but had to have been transported there through the air. When Spallanzani presented his results to the public, he was criticized. Other scientists said that he made the air unfit for living growth, and that they needed the air to change from nonliving to living. Pasteur did the third experiment, in 1862. He took Spallanzanis experiment, and the critics statements, and combined the two. He boiled pond water to kill all the living organisms. He poured that water into two curved neck flasks. He then proceeded to break the neck off of one of the flasks at the base. The flask with the broken neck started to become cloudy in a few days, however, the other flask continued to stay clear. He proved that the microbial organisms could not come from something nonliving. The curve in the neck of the flask allowed air to flow in, however, it caught all the microorganisms in the neck. Spontaneous generation is the idea that a living organism can come from something nonliving. This idea was entirely believed until the mid 1800s. Three important experiments helped to disprove this idea. Due to the work of three men, we now have the knowledge that living things can only come from other living things in our environment. Science Essays