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5 billion years ago
Solar System was a swirling mass of gas that was pulled togather by gravity. -
4.6 billion years ago
Space debris collide to form planet earth and other planets as well -
4 billion years ago
earth is created, it's 700,000 times as long as the period of recorded history, 50 million times as long as average human life span. -
3.5 billion years ago
stromatolites form from coloniew of lynbgya -
3 billion years ago
some forms of life become photosynthetic -
Earth Forms (2.2 billion years ago)
earth started to look how it does today -
O2 levels
O2 levels reach todays level -
Prokaryotes ( 2-1.5 billion Years ago)
type of aeobic prokaryote was engulfed by and began to live and repoduce inside of a larger anaerobic prokaryote. -
Ozone ( 1 billion years ago)
Ozone formed, it protected organisms from harmful uv tays so they could exist on land -
Spontaneous generation (1626-1697)
Franceso Redit was the first to deny spontaneous generation and set up an experiment where he left out jars of meat to see if flies were borm from the meat and he discovered that the flies just lay their eggs in the meat. many scientists later on did experiments on the topic. -
First Microscope (1665)
robert hooke srudied nature closely by using an early light microscope. -
Louis Pasteur (1822-1895)
He was a french scientist that won the Paris academy of science award for clearing up the controversy of spontaneous generation. He boiled broth in a curve necked flask for 1 year and concluded th microorganisms contaminated the broth from the air. This was the accepted way of thinking after he proved everyone wrong. -
Alexander Oparin (1894-1980)
Oparin thought that the early atmosphere contained ammonia and at high temperature these gases might form simple organic compounds such as amino acids. He set up an experiment that later on american scientists will test. -
Urey and miller (1930-)
Set up experiment to test oparin's hypthesis and produced a variety of organic compounds. since then scientists use similar experiments to create new compounds -
Thomas Cech (1938-)
Cech found a type of rna found in some unicellular eukaryotes that are able to act as a chemical catalyst. Later studies that were based on Cech's discovery indicate that ribozymes could act as catalysts for their own replication -
Lynn margulis (1938-)
Proposed that early porkaryotic cells may have developed a mutaually beneficial reationship. evidence shows that 2 - 1.5 billion years ago a small aerobic prokaryote was enfulfed by and began to live and reproduce insid a larger one. This theory is called endosymbiosis. -
Radiometric Dationg
It is a method of establishing the age of materials, it determines the half life of an isotope. -
Lazzaro spallanzani (1729-1799)
Spallanzani designed experiment to test spontaneous generation, he hypothesized that micro organisms formed not from air but from other micro organisms. Spallanzani boiled fresh broth and sealed 1 broth and left another open. He concluded that the boiled broth became contaminated obly when microorganisms from th air entered the flask. People disagreed with him saying he boiled it for to long and this allowed others to take a look into the matter -
Sidney Fox (1912-1998)
Did extensive research on the physical structures that may have given tise to the first cells. The structures inlude microspheres which are orgivized as a membrane and coacervates which are collections of droplets that are compsed of lipids amino acids and sugars. These show important aspects of cellular life can arise without direction of genes
