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Our solar system was a swirling mass of gas and dust. This material was pulled together by gravity and formed the sun. If the Earth was never pulled together by gravity then none of us would be here.
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The sun ignites and the solar system takes form. The earth is finally made. If the sun had never ignited then our civilization on earth would not servive.
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The moon is formed from collisions and the earth forms a solid crust. If the Earth never formed a solid crust then civilization couldnt survive on it.
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Earth’s atmosphere initially lacks oxygen (anoxic). With out oxygen no life would have survived on earth.
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Simple organisms represent the original cells on Earth.
Organic molecules join the aqueous chemical soup as amino acids, nitrogenous bases, carbs, and hydrocarbs.
Photosynthesis generates oxygen while providing energy for further development and experimentation. -
Single cell bacteria is discovered and marine photosynthesis starts to occur.
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Prokaryotes and single cell bacteria are discovered, photosynthesis and respiration are understood and eukaryotes are discovered. Without these discoveries we wouldn't be able to understand cells. Without this understanding we wouldn't know how the human body works and how to fix it when there are problems.
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Oxygen levels reached today’s levels. If the Oxygen levels on earth never reached the amount that there is today then all of the life on Earth would be dead.
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Evidence of eukaryotes, the earliest fossil, is discovered.
They discovered that hereditary matierial is protected within its own chamber, the nucleus.
Biochemical technology resulted in larger cells with more efficient mitochondria and chloroplasts. Cells started to collaborate with one another and specialize. -
They discovered a small aerobic prokaryote that was engulfed and began to live and reproduce inside of a larger anaerobic prokaryote.
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Ozone (O3) formed to protect the organisms from harmful UV rays so they could exist on land. If this never happened then all of the life on earth would be dead and civilizations would never have started.
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The first light microscope was created by Robert Hooke.
Hooke used the microscope to view a thin slice of cork from the bark of a cork oak tree. He discovered that cells of tree stems, roots, and ferns all had little boxes (plant cells). -
Francesco Redi noticed and described the different forms of flies by conducting an experiment where he placed meat inside open jars and not covered jars with meat inside. He saw that maggots only lived in the open jars.
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Pasteur used a variation of Spallanzani’s design to prove that microorganisms are carried in the air and do not arise by spontaneous generation.
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Lynn Margulis proposed that early prokaryotic cells may have developed a mutually beneficial relationship.
Urey and Miller set up an experiment using Oparin’s hypothesis by creating a chamber containing the gases Oparin assumed were present in the earth’s atmosphere and as the gases circulated in the chamber, electric sparks supplied energy to drive chemical reactions to test Oparin’s hypothesis about the conditions for formation of organic molecules on early Earth. -
Spallanzani showed that microorganisms would not grow in broth when its container was heated and then sealed. He inferred that microorganisms do not arise spontaneously but, rather, carried in the air.
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Thomas Cech found that a type of RNA found in some unicellular eukaryotes is able to act as a chemical catalyst. Sidney Fox and others have done extensive research on the physical structures that may have given rise to the first cells. Cell-like structures form spontaneously in the laboratory from solutions of simple organic chemicals. Radiometric dating is a method used to determine the absolute age of an object by comparing percentages of a radioactive parent isotope and a daughter isotope.
