General Biology 1 Lab
22 October 2013
The Theories of Life
There are many theories on how life and molecules were formed. Most of these theories contain beliefs and experiments on how our society as a whole was formed. Some have been rejected, but others are still being tested today. A few we thought were most appropriate and more logical than others were spontaneous generation, electrical spark, panspermia, and deep-sea vents.
The Big Bang Theory is a hit sitcom that airs on CBS periodically throughout the week. The television show is produced by Chuck Lore and Bill Prady, and made its first premier on CBS September 24, 2007. After the first segment of the show has played a song called “The History of Everything” begins to play as the shows theme song. We chose this song as our theme song for our project. “The History of Everything” is composed by the Bare-naked Ladies, and was first released on October 9, 2007, to the public. We chose this song due to the fact that it gave a theory used widely on how the universe began. Although, we did not use the Big Bang Theory that they make reference to in the song, we still feel like it was the best choice because one thing that all theories have in common is the fact that something occurred from some sort of naturally occurring element.
However, the spontaneous generation is the belief that living things are thought to come to life on its own (Harris). This theory was first thought of by a western thinker known as Anaximander who believed that everything arose out of some element in nature. For instance, he believed that living creatures had to be mixed with water and acted on by the sun to be formed. Although Anaximander himself did not write these beliefs, they were passed on to a later source named Hippolytus (Wilkins).
Throughout time there have been many theories tested for and against spontaneous generation. Redi Francesco ran a famous experiment to disprove spontaneous generation. He placed meat in eight jars. Four jars were covered, and four jars were left opened. Maggots began to develop in the jars that were left uncovered because flies were able to land on the meat, but, flies could not touch the covered meat, therefore; life could not begin in the sealed jar. Redi’s experiment proved life comes from life (Sant). One most known today is by a man named Louis Pasteur. Pasteur believed that life came from life (Wilkins). He performed a series of test with two flasks both filled with sterile nutrient broth. When Pasteur broke off the neckpiece of one of the flask it immediately began to obtain dust particles and became cloudy, but the unbroken flask did not and remained cleared. Through this simple experiment Louis Pasteur was able to refute the notion of spontaneous generation (Barnett).
Another popular theory of life was the Electric Spark theory. Professor Stanley Miller from the University of Chicago sparked the debate with several experiments he conducted from 1953 to 1954. He used gases that were thought to be common in Earth’s atmosphere, including hydrogen, methane, and ammonia, and zapped them with electricity in canteens with water. After weeks of running the experiments he realized the water was starting to darken. He tested the water and found amino acids, which are important to build proteins, in the water. The energy from the electricity provided enough energy for the molecules to rearrange to form the amino acids. The amino acids can later be used to build proteins, which will be able to build more proteins. Without these macromolecules, life would not be possible. Several years later, his coworkers used new modern technology and repeated his experiments. They discovered that the experiment that was most like a volcano produced a “wider variety of compounds”. In that experiment, twenty-two new amino acids were discovered. Ten of those amino acids had never been found in an