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440
440 BC
Democritus starts his theory about atoms. -
Jan 7, 1543
Sun is the center
Copernicus discovered that the sun is in the center rather than the earth being the one in the center. -
The Law of Falling Bodies
Galileo Galilei said that heavier the body the faster it falls than lighter ones. By proving that all bodies fall at the same rate. -
Blood Circulation
William Harvey discovered that blood circulates through the body and names the heart as the organ responsible for pumping the blood. -
Universal Gravitation
Issac Newton came up with the conclusion that all the obejcts in the universe extert gavitational attraction on each other. -
Hydrodynamica
Daniel Bernoulli published Hydrodynamica in which explained the relationship between pressure and velocity of fluids. The Bernoulli effect. -
Andres
Andres Celsius invents the celsius temperature scale. -
Mikhail
Lomonosov formulates the laws of conservation of mass and energy. -
Photosynthesis
Jan Ingenhousz: Plants react differently in sunlight differently than in the shade. Plant leaves take in carbon dioxide and roots absorb water the sunlight runs a reaction that yields glucose and oxygen. -
Period: to
The Milky Way Is A Gigantic Disk Of Stars
William Herschel & his sister Carolyn mapped out the entire sky and proved that out solar system resides in a giant disk of stars called the milky way. -
Atomic Theory
John Dalton introduces the atomic theory. In which stated that the elements consisted of tiny particals called atoms. -
Period: to
Electricity Transforms Chemiclas
Humphry Davy finds that electricity can transform chemicals. He used an early battery to separate salts (electrolysis) -
Woehler
Friedrich Woehler acceidently synthesizes urea from inorganic materials. It proved that substances made by living things can be reproduced with nonliving substances. -
The Periodic Table
Dmitri Medeleev showes his first periodic table. Was compiled on the basis of arranging the elements in order, atomic wight and grouping them by similarity of properties. -
Pasteur & Jules Francois Joubert
Found that some bacteria from the air seemed to inhabit the growth of anthrax bacteria. -
Chemical Dye
The German physician & chemist Paul Ehrlich found that a chemical dye called methylene blue was absorbed by particular bacteria but not others. The concept "magic bullet" drug that would selectively destroy particular invading organisms. -
Moissin H.
Moissin H. developed electric furnace for making carbides and prepering pure metals, isolated fluorine. -
Troposhere & Stratosphere
Leon Teisserenc de Bort discovers that the atmosphere consists of layers. After 200 ballon experiments he concluded that the atmosphere is divided into two layers. -
Santiago Ramon & Cajal
Spanish neuroanatomist showed that the electrical signal coursing through a nerve begins in the dendrites and moves to the axon. -
Period: to
Radioactivity
Marie and Pierre Curie had discovered isolate radioactivity materials. This also lead to the discovery of the elements polonium and radium. -
The Electrons
J.J Thomson discovered the electron. He looked further into electricity and magnetism and he ended up finding a particle that contained in atoms. -
P. Flourescens
Rudolf von Emmerich and O. Loew discovered P. Flourescens. It can also help treat things such as skin wounds, killing or suppressing the microorganisms causing surface infections. -
Seconds Not A Second
Albert Einstein said that a second is not a second. The second is by one clock belongs to less than a second measured by another clock. -
Magnetic Field Reversal
Bernard Bushes discovered that the Earth's magnetic field had changed direction & reversed itself. -
Radiometric Dating
Bertram Boltwood discovered how to calculate the age of a rock by measuring the rate of its radioactive decay. -
Scilvarsan 606
Ehrlich, develoved a drug called Scilvarsan 606, which was effective against syphilis. -
The Nucleus
Ernest Rutherford, using a thin piece of gold foil, established that the nucleus was positively charged also that the electrons were located outside the nucleus. -
Continental Drift
Alfred Wegener said that at first all the continents once were all together forming a gaint landmass. Then with time they started to drift apart. -
Bohr
Bohr began postulating atomic models. Certain parameters of the electrons orbit were "quantized." -
Covalent Bonds
Gilbert Netwon Lewis, discovered that covalent bonds are brought by the sharing of pairs of electrons between two atoms. Each atom in a covalent bond will share one electron. -
Isotopes
Aston discovered isotopes and he also builds the mass spectrograph. -
Atomic Structure
Niels Bohr developed an explanation of atomic structures. -
de Broglie
de Broglie discovered that electrons had a dual nature-similar to both particles & waves. -
Heisenberg
Heisenberg describes atoms by means of formula. Connected to the frequences of spectral lines. -
Pauling's seminal paper
Pauling's seminal paper was the realization that the orbits of electrons in isolated singnal atoms were not of the right shape for bonding with other atoms. -
Virulent Bacteria
With a experiment with mice the bilogist Fred Griffith found that virulent bacteria even when it has been killed with heat could transform nonvirulent bacteria into virulent bacteria. He ended up concluding that the genetic material was being passed from the first to the second. -
Schrodinger
Schrodinger viewed electrons as continous clouds and introduced the "wave mechanics" (mathematical model of the atom.) -
Periodic Ice Ages
The astrophysicist Miultin Milankoviten developed a theory that related to earth's motion to long-term climate change & Ice Ages. -
Pauling Oxygen
Found how oxygen bonds to hemoglobin. -
Pauling Protein Molecules
Discovered how protein molecules fold up and unfold, key factor in their behavior & proerties. -
The Krebs Cycle
Hans Krebs. He identifies that there are many steps that the cell takes to convert sugars, fat and protenis into energy. It's a series of chemical reaction using oxygen. This cycle contributes to the breakdown of carbonhydrates, fats and proteins into carbon dioxide and water. -
Some Genes Can Jump
Barbara McClintock discovered transposons (genes that can jump on a chromosome) Transposons are segments of DNA that can move to a different position in the genome of a single cell. This might also cause mutations & increas/decrease. -
Controlled Chain Reaction
Enrico Fermi conducted the first controlled chain reaction. In which it released energay from the atoms nucleus. -
First Identification
Pauling, first identification of molecular disease, sickle-cell anemia. -
DNA Structure
The DNA structure was first discovered by James Watson, Francis Crick, and Rosalind Frankline. They said that it's shaped like a twisted ladder. Each of two legs of it forms a helix. And each rug consists of two small molecules fastened together. C-G, G-C, A-T, T-A -
RNA Conveys Genetic Information
Scientist discovered ribonoclelc acid or RNA. RNA plays an important role in protein synthesis and other chemical activites in the cell. -
Protons and Neutrons
Friedman and his colleagues found that protons and neutrons are made out of three quarks a piece. -
Oncongenes
Harold Varmus & Michael Bishop discovered oncongenes (normal genes that control growth in every living cell, also can contribute to converting normal cells into cancer cells if mutated.) -
RNA Splicing
A group of scientists dicscovered RNA Splicing. The DNA is first transcribed into pre-messenger RNA, then RNA molecules are spliced to create mature messanger. Improperly spliced messanger RNA molecules create altered proteins and result in disease. -
Achaea
Carl Woese discovered that bacteria are not only simple. Many organisms classified in the new kingdom of Achaea are extremophiles some live in very high temp. others in low temp. Archaea are harmless to other organisms. And none are known to cause disease. -
Friedman
Friedman, Henry Kendall & Richard Taylor shard the Nobel Prize for discovering quarks along with leptons are the smallest know building blocks of matter.