-
(5 BYA) Development of the Sun
The solar system was a mass of gas and dust. The mass was pulled together by gravity, and exploded into the sun, a ball of burning gas, specifically hydrogen and helium. Its huge mass and energy producing nuclear reactions make it the center of the solar system and the key component to life. For instance, its light rays triggered the complicated, yet essential process of photosynthesis. -
(4.6 BYA) Formation of Earth
As the swirling rocks and gases revolved around sun, they collided and formed into the planets we know today. Earth around this time began to take its familiar spherical shape. -
(4 BYA) Moon and Earth's Surface
The moon is formed by a collision of debris and the Earth forms its surface. Through radiometric dating it was found that those rocks and crystals were 4 billion years old. The moon impacts Earth's tides by its gravital influence. At this time organic molecules are forming such as self producing RNA on Earth. -
(3.5 BYA) Forming of Cells
Cells representing the first prokaryotes emerge at this time. Archea, one of the first forms of life, finds its energy in the process of chemosynthesis. This is the basis of the development of cell and life on Earth. -
(3 BYA) Cell Photosynthesis and Respiration
At this point some cell are becoming photosynthetic, such as the modern equivalent of cyanobacteria cells. As photosynthesis developed so did the outcome of oxygen, which caused the earliest forms of aerobic respiration to make oxyogen less damaging. This made needed organic compounds and cells survive. -
(2.2 BYA) Earth
Earth is now formed much as it is today, with land masses and bodies of water. Our lovely blue planet becomes a lovely blue planet. -
(2 BYA) O2 Levels
The O2 reached their current levels. After a long period of ancient cells converting CO2 to oxygen through photosynthesis. The newfound high levels of O2 led to the emergence of more complicated organisms that thrived from the popular gas. -
(2-1.5 BYA) Development of Eukaryotic Cells
Eukaryotic cells appear by an aerobic prokaryote engulfed living inside another prokaryote cell by endosymbiosis. Eukaryotic cells are much more complicated than prokaryotic cells, having membranes and make up plants and animals that sustain Earth. -
(1 BYA) Ozone
Some of the O2 combined to make O3, or ozone, which absorbs the ultraviolet radiation from the sun. Without the ozone layer the rays would damage DNA and life could not exist on Earth. The life on Earth now consists of mtiochondira forming from endosymbiotic aerobic prokaryotes and cyanobacteria evolving into chloroplasts. -
(1600-1700) Redi's Experiment
Redi through experiments proved that flies come only from eggs laid by other flies. This experiment was the first to begin disproving spontaneous generation. -
(1700-1800) Microorganisms
Microorganisms were discovered by the invention of the microscope.Spallanzani experimented and proved against spontaneous generation and showed that microorganisms are formed by other microorganisms. -
(1800-1900) Contamination
Pasteur proved all objections to Spallanzani’s experiment wrong and show that microorganisms in the air is contaminating the broth, and that there was no vital force. -
(1900-present) Discoveries in Cells
In the 20’s, Oparin hypothesized that the gases of the atmosphere created organic compounds at high temperatures.Miller and Urey tested his hypothesis proving to be true and produced amino acids.Fox, researching cells found out that some of the first cell-like structures, like microshperes, do not need genes to live. Margulis saw that early prokaryotic cells are important for creating andosymbiosis and energy synthesis.Thomas Cech discovered that ribozyme act like a chemical catalyst & replicate
