-
(5 BYA)
The solar system was a swirling mass of gas and dust. -
(4.6 BYA)
Earth grew larger from forming debris. -
(4 BYA)
The fully formed Earth is estimated to be roughly 4 billion years old. -
(4 BYA)
The Earth was bombarded with space debris but this helped it to grow. Oldest crystals and rocks are formed, and the first organic material is begining to form -
(3.5 BYA)
fossils of stromatolites -
(3 BYA)
some cells became photosynthetic. also known as cyanobacteria -
(2.2 BYA)
the Earth look much like it does today. -
(2 BYA)
O2 levels reached today’s levels -
(1.5 BYA)
first Eukaryotes, Prokaryote that held smaller prokaryotes. -
(1 BYA)
Ozone (O3) formed – protected organisms from harmful UV rays so they could exist on land -
(1700-1800)
Lazzaro Spallanzani- showed that microorganisms grew from other microorganisms and not from a “vital force” in the air which is what microorganisms were said to come from. He boiled broth and then sealed the top so that no microorganisms could get in to grow. -
(1800-1900)
Louis Pasteur-answered the question about spontaneous generation his conclusion was that the broth become cloudy due to contamination by microorganisms in the air
Pasteur’s experiment-with a curved neck flack he boiled broth inside of it, the broth was clear for up to a year and when the neck was taken off the broth became cloudy -
(1920)
Alexander I. Oparin and John B. S. Haldane thought that the early atmosphere contained many different gases which then formed proteins. -
(1900s)
Sidney Fox- he worked on micro spheres which are spherical cells and coacervates which are collections of droplets of molecules. -
(1953)
Harold C. Urey with his student Stanley L. Miller set up an experiment Oparin’s hypothesis as a starting point a flask held water and was boiled and the water vapor traveled up a tube past two electrodes into another flask with a gas suspected to be from the beginning of the earth they would mix travel through a condenser and into beaker so that they could test the newly formed organic compound. -
(late 1900s)
Lynn Margulis proposed that prokaryotes had forged within other prokaryotes to make the first eukaryotes in the theory of endosymbiosis. -
(1600-1700)
Francesco Redi- created an experiment to show how flies didn’t come from meat but came from larva that was laid in the meat by flies that landed on the meat. He did this by putting a net over the jars to stop flies from landing. During the time of Redi Scientists began using the microscope where they first observed microorganisms. Hooke looked at plants and corks and saw that they were broken into cell like compartments so he named them cells. -
(1953)
Stanley Miller tested Oparin’s hypothesis and showed that if the atmosphere were to have these certain gases that they would form amino acids and other basic organic compounds. -
(1980s)
Thomas Cech discovered that a certain type of RNA cells act as a chemical catalyst and named it ribozyme, which has have many uses. It is even hypothesised that RNA or a similar system made modern cellular life. -
(1900s)
Radiometric dating-is taking isotopes and finding there half life so that we can see how old a radioactive object is.
