Bacteria grew in the open flask and did not grow in the sealed flask.
Conclusion: bacteria comes from the air
Disproved spontaneous generation
Boiled broth and bent the neck of the flask to allow air to pass but not any particles.
Conclusion: The open curved neck flask with the boiled broth did not grow any bacteria.
Explain the experiment of the Miller and Urey. Be sure you are familiar with their set- up apparatus and what their conclusions were.
Miller and Urey recreated the conditions of the primitive earth in a closed experiment. They used gases believed to have existed on the primitive earth and used an electrical spark to simulate the energy from lightening. The result was they organic compounds were produced.
Who was Oparin? What did he do and conclude?
Oparin is credited with the heterotroph hypothesis. He, along with other scientists, thought that the early atmosphere contained ammonia, hydrogen gas, water vapor and methane. According to Oparin, at high temperatures, these gases might have formed simple organic compounds such as amino acids. When the earth cooled and water vapor condensed these simple organic compounds collected in the water. Over time these compounds could have entered complex chemical reactions, fueled by energy from lightning and ultraviolet radiation. These reactions ultimately would have resulted in the macromolecules essential to life such as proteins.
Explain the endosymbiotic theory.
Early prokaryotic cells may have developed a mutually beneficial relationship early on. Evidence suggests that a small aerobic prokaryote was engulfed by and began to live and reproduce inside a larger anaerobic prokaryote. It is thought that these early symbiotic prokaryotes over time developed into mitochondria capable of aerobic respiration and chloroplasts capable of photosynthesis.
Explain the first organisms on earth (were they prokaryotes or eukaryotes; anaerobic/aerobic; able to perform photosynthesis).
The first organisms were anaerobic heterotrophic prokaryotes as there was no oxygen in the early atmosphere. These prokaryotes had to rely on others for a source of food.
Explain the different parts of Darwin’s theory of natural selection.