100 Greatest Science Discoveries - Part2

Couple of Days back i started reading 100 Greatest Science Discoveries of All Time Book By Kendall Haven.

I wanted to share few important quotations i found from this book from 50 - 75 top discoveries.

Tomorrow i will share remaining great science discoveries from the book.

50) Atmospheric Layers

Earth’s atmosphere has distinct layers of air, each with unique temperatures, densities, humidities, and other properties.

Léon Philippe Teisserenc de Bort (November 5, 1855 in Paris, France – January 2, 1913 in Cannes, France) was a French meteorologist who became famous for his discovery of the stratosphere.

Teisserenc de Bort pioneered the use of unmanned instrumented balloons and was the first to identify the region in the atmosphere around 8-17 kilometers of height where the lapse rate reaches zero, known today as the tropopause.

He discovered an indication of a temperature inversion or at least of a zero lapse rate above this altitude.

During the years that followed, he named the two layers of the atmosphere known at that time the "troposphere" and the "stratosphere". This naming convention has since been maintained, with (higher-altitude) layers that were subsequently discovered being given names of this sort. After Teisserenc de Bort's death in 1913, the heirs donated the observatory to the state so that the research tasks could be continued.

Fun Facts: Scientists now know that the atmosphere has many layers, but the troposphere is the layer where all of Earth’s weather occurs.

51) Hormones

Chemical messengers that trigger action in various organs within the body.

Sir William Maddock Bayliss (May 2, 1860 - August 27, 1924) was an English physiologist. He graduated in physiology from Wadham College, Oxford.

He and Ernest Henry Starling discovered the peptide hormone secretin and peristalsis of the intestines. The Bayliss effect is named after him.

He was also involved in the Brown Dog affair, successfully suing Stephen Coleridge for libel over accusations he made about Bayliss's vivisection work.

William Bayliss's wife was Gertrude Starling, sister of Ernest Starling.

He was knighted for his contribution to medicine in 1922.

The Bayliss and Starling Society was founded in 1979 as a forum for scientists with research interests in central and autonomic peptide function.

Ernest Henry Starling (April 17, 1866 - May 2, 1927) was an English physiologist. He worked mainly at University College London, although he also worked for many years in Germany and France. His main collaborator in London was his brother-in-law, Sir William Maddock Bayliss.

Starling is most famous for developing the "Frank-Starling law of the heart", presented in 1915 and modified in 1919. He is also known for his involvement along with Bayliss in the Brown Dog affair, a controversy relating to vivisection. In 1896 at the age of 30 Ernest was married to Katherine Laird, a vaudevillian dancer who died shortly after of a blood infected illness.

Other major contributions to physiology were:

The Starling equation, describing fluid shifts in the body (1896)
The discovery of peristalsis, with Bayliss
The discovery of secretin, the first hormone, with Bayliss (1902) and the introduction of the concept of hormones (1905)
The discovery that the distal convoluted tubule of the kidney reabsorbs water and various electrolytes
Starling was elected fellow of the Royal Society in 1899.

Two of his great-grandchildren, Boris Starling (b. 1969) and Belinda Starling (1972-2006) are writers.

Fun Facts: Robert Earl Hughes, the world’s largest man, weighed 484 kg (1,067 lb.) at his death in 1958. Years after his death, scientists discovered that he had too little of the hormone thyroxin in his system. Without this vital hormone, his body couldn’t burn the food he ate, and so his body continually stored it as fat.

52) E = mc2 - The first established relationship between matter and energy.

Albert Einstein (14 March 1879 – 18 April 1955) was a German-born theoretical physicist. He is best known for his theory of relativity and specifically mass–energy equivalence, E = mc 2. Einstein received the 1921 Nobel Prize in Physics "for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect."

Einstein's many contributions to physics include his special theory of relativity, which reconciled mechanics with electromagnetism, and his general theory of relativity, which extended the principle of relativity to non-uniform motion, creating a new theory of gravitation. His other contributions include relativistic cosmology, capillary action, critical opalescence, classical problems of statistical mechanics and their application to quantum theory, an explanation of the Brownian movement of molecules, atomic transition probabilities, the quantum theory of a monatomic gas, thermal properties of light with low radiation density (which laid the foundation for the photon theory), a theory of radiation including stimulated emission, the conception of a unified field theory, and the geometrization of physics.

Einstein published over 300 scientific works and over 150 non-scientific works. Einstein is revered by the physics community, and in 1999 Time magazine named him the "Person of the Century". In wider culture the name "Einstein" has become synonymous with genius.

Fun Facts: Einstein’s famous equation tells us exactly how much energy exists in any given object (or mass). However, only one reaction releases all of this energy: a matter–anti matter collision, the only perfect con version of matter into energy in our universe.

53) Relativity - Einstein’s theory that space and time merge to form the fabric of the universe that is warped and molded by gravity.

Fun Facts: We know that the look and sound of moving objects appear and sound different depending on whether the receiver is stationary or moving. Special relativity is based on the mind-boggling concept that, no
matter how fast you travel, the speed of light appears to remain the same!

54) Vitamins - Tracedietary chemical compounds that are essential to life and health.

Christiaan Eijkman was born on August 11, 1858, at Nijkerk in Gelderland (The Netherlands), the seventh child of Christiaan Eijkman, the headmaster of a local school, and Johanna Alida Pool.

A year later, in 1859, the Eijkman family moved to Zaandam, where his father was appointed head of a newly founded school for advanced elementary education. It was here that Christiaan and his brothers received their early education. In 1875, after taking his preliminary examinations, Eijkman became a student at the Military Medical School of the University of Amsterdam, where he was trained as a medical officer for the Netherlands Indies Army, passing through all his examinations with honours

Sir Frederick Gowland Hopkins OM FRS (June 20, 1861 Eastbourne, Sussex - May 16, 1947 Cambridge) was an English biochemist who was awarded the Nobel Prize in Physiology or Medicine in 1929, with Christiaan Eijkman, for the discovery of vitamins. He also discovered the amino acid tryptophan, in 1901.

Fun Facts: Think all sweets are bad for you? Her shey’s Sugar Free Chocolate Syrup has 10 percent vitamin E per serving.

55) Radio active Dating - The use of radio active decaying elements to calculate the age of rocks.

Bertram Borden Boltwood (July 27, 1870 Amherst, Massachusetts - 1927, Hancock Point, Maine) was an American pioneer of radiochemistry.

He was a graduate of Yale University, and taught there 1897-1900. He measured the age of rocks by the decay of uranium to lead, in 1907. He got results of ages of 400 to 2200 million years, the first success of radiometric dating. More recently, older mineral deposits have been dated to about 4.4 billion years old, close to the best estimate of the age of earth.

Boltwoodite is named after him.

Fun Facts: Radio metric dating can be performed on samples as small as a billionth of a gram. The uranium-lead radio metric dating scheme is one of the oldest available, as well as one of the most highly re spected. It has been refined to the point that any error in dates of rocks about three billion years old is no more than two mil lion years. The measurement is 99.9 percent accurate.

56) Function of Chromosomes

Genes are grouped (linked) in groups that are strung along chromosomes.

Thomas Hunt Morgan (September 25, 1866 – December 4, 1945) was an American geneticist and embryologist. Morgan received his PhD from Johns Hopkins University in 1890 and researched embryology during his tenure at Bryn Mawr. Following the rediscovery of Mendelian inheritance in 1900, Morgan's research moved to the study of mutation in the fruit fly Drosophila melanogaster. In his famous Fly Room at Columbia University Morgan was able to demonstrate that genes are carried on chromosomes and are the mechanical basis of heredity. These discoveries formed the basis of the modern science of genetics. When he was awarded the Nobel Prize in Physiology or Medicine in 1933 he was the first person awarded the Prize in genetics, for his discoveries concerning the role played by the chromosome in heredity.

During his distinguished career Morgan wrote 22 books and 370 scientific papers, and as a result of his work Drosophila became a major model organism in contemporary genetics. The Division of Biology he established at the California Institute of Technology produced seven Nobel Prize winners.

Fun Facts: Fruit flies can lay up to 500 eggs at a time, and their entire lifecycle is complete in about a week.

57) Antibiotics - Chemical substances that kill infectious microscopic organisms without harming the human host.

Paul Ralph Ehrlich (born May 29, 1932 in Philadelphia, Pennsylvania) is a renowned entomologist specializing in Lepidoptera (butterflies). He is also well known as a researcher and author on the subject of human overpopulation, notably for his 1968 book The Population Bomb, and is Bing Professor of Population Studies in the department of Biological Sciences at Stanford University.

Fun Facts: Resistance to antibiotics works by the ordinary rules of natural selection: that segment of the bacteria population that has a natural ability to counter the drug’s effect will survive, so that their genes eventually are shared by the entire population. Many disease-causing viruses and bacteria have devel oped virtual immunity to many antibiotics, making medical planners fear massive disease out breaks in the near future.

58) Fault Lines - Earthquakes happen both along, and because of, fault lines in the earth’s crust.

Scientists now know that they can predict the locations of future earth quakes by mapping the locations of fault lines. However, just a century ago this simple truth was not known.

Harry Reid’s discovery that earth quakes happen along existing fault lines provided the first understanding of the source and process of earth quakes. This discovery laid the foundation for the discovery of Earth’s crustal plates and plate tectonics in the late 1950s.Reid’s discovery was called a major break through in earth science and provided the first basic under standing of Earth’s internal processes and of how rocks be have understress.

Fun Facts: The destructive San Francisco earth quake of 1906 horizontally shifted land surfaces on either side of the San Andreas fault up to 21 ft (6.4 m).

59) Super Conductivity - Some materials lose all resistance to electrical current at super-low temperatures.

Heike Kamerlingh Onnes (September 21, 1853 – February 21, 1926) was a Dutch physicist. His scientific career was spent exploring extremely cold refrigeration techniques and the associated phenomena.

In 1870, Kamerlingh Onnes attended the University of Groningen. He studied under Robert Bunsen and Gustav Kirchhoff at the University of Heidelberg from 1871 to 1873. Again at Groningen, he obtained his masters in 1878 and a doctorate in 1879. His thesis was "Nieuwe bewijzen voor de aswenteling der aarde" (tr. New proofs of the rotation of the earth). From 1878 to 1882 he was assistant to Johannes Bosscha, the director of the Polytechnic in Delft, for whom he substituted as lecturer in 1881 and 1882.

Fun Facts: AT CERN, the European high-energy physics research lab,scientists used a one-time jolt of elec tricity to start an electrical current flowing through a super conductor circuit. That electrical current
ran—with no additional voltage in put—for five years with no loss of power. In common house wires, an elec trical current would stop within a few milliseconds once the voltage is removed because of the resistance
of electrical wires.

60) Atomic Bonding - The first working theory of how electrons gain, lose, and hold energy and how they or bit the nucleus of an atom.

Niels Henrik David Bohr was a Danish physicist who made fundamental contributions to understanding atomic structure and quantum mechanics, for which he received the Nobel Prize in Physics in 1922. Bohr mentored and collaborated with many of the top physicists of the century at his institute in Copenhagen. He was also part of the team of physicists working on the Manhattan Project. Bohr married Margrethe Nørlund in 1912, and one of their sons, Aage Niels Bohr, grew up to be an important physicist who received the Nobel prize in 1975. Bohr has been described as one of the most influential physicists of the 20th century.

Fun Facts: Niels Bohr worked at the secret Los Alamos laboratory in New Mexico, on the Manhattan Project (the code name for the effort to develop atomic bombs for the United States dur ing World War II).

61) Isotopes - Isotopes are different forms of the same chemical element that have identical physical and chemical properties but different atomic weights.

Frederick Soddy (2 September 1877 – 22 September 1956) was an English radiochemist.

Soddy was born in Eastbourne, England. He went to school at Eastbourne College, before going on to study at University College of Wales at Aberystwyth and at Merton College, Oxford. He was a researcher at Oxford from 1898 to 1900. He married Winifred Beilby in 1908.

He received the 1921 Nobel Prize in chemistry for his research in radioactive decay and particularly for his formulation of the theory of isotopes.

Fun Facts: Isotopes are more important than most people think. Every ancient rock, fossil, human remain, or plant ever dated was dated using isotopes of various elements. Natural radio activity is created by isotopes.

The atomic bomb uses an isotope of uranium.

62) Earth’s Core and Mantle - The earth is made up of layers, each of a different density, temperature, and composition.

Beno Gutenberg (June 4, 1889 – January 25, 1960) was a German-born seismologist who made several important contributions to the science. He was a colleague of Charles Francis Richter at the California Institute of Technology and Richter's collaborator in developing the Richter magnitude scale for measuring an earthquake's magnitude.

Gutenberg was born in Darmstadt, Germany and obtained his Doctorate in Physics from University of Göttingen in 1911. His advisor was Emil Wiechert. Gutenberg held positions at the University of Strasbourg which he lost when Strasbourg became French in 1918. After some years where he had to sustain himself with managing his father's soap factory, he obtained in 1926 a junior professorship at University of Frankfurt-am-Main, which was badly paid. Although he was already in the Twenties one of the leading seismologists worldwide, and definitely the leading seismologist in Germany, he was then still dependent on the position in his father's factory. In 1928 the attempt to become the successor of his academic teacher Emil Wiechert in Göttingen failed. There are hints that Gutenbergs Jewish background might have played a role, because already in the Twenties there were strong antisemitic tendencies in German universities. For similar reasons he was also not accepted for a professorship in Potsdam to become the successor of Gustav Angenheister.

Fun Facts: The crust of the earth is solid. So is the inner core. But in between, the outer core and mantle (90 per cent of the mass of the earth) are liquid to molten semi-solid. We do not live on a particularly solid planet.

63) Continental Drift - Earth’s continents drift and move over time.

Alfred Lothar Wegener (November 1, 1880 – November 2 or 3, 1930) was a German scientist and meteorologist. He was born in Berlin. He is most notable for his theory of continental drift (Kontinentalverschiebung), proposed in 1912, which hypothesized that the continents were slowly drifting around the Earth. However, at the time he was unable to demonstrate a mechanism for this movement; this combined with a lack of solid evidence meant that his hypothesis was not accepted until the 1950s, when numerous discoveries provided evidence of continental drift.

Wegener had early training in astronomy (Ph.D., University of Berlin, 1904). He became very interested in the new discipline of meteorology (he married the daughter of famous meteorologist and climatologist Wladimir Köppen) and as a record-holding balloonist himself, pioneered the use of weather balloons to track air masses. His lectures became a standard textbook in meteorology, The Thermodynamics of the Atmosphere. Wegener was part of several expeditions to Greenland to study polar air circulation, when the existence of a jet stream itself was highly controversial. On his last expedition, in Greenland, Alfred Wegener and his companion Rasmus Villumsen went missing in November 1930. Wegener's body was found on May 12, 1931. His suspected cause of death was heart failure through overexertion.

Fun Facts: The Himalayas, the world’s highest mountain system, are the result of the ongoing collision of two huge tectonic plates (the Eurasia plate and the Indian subcontinent), which began about 40 million years ago.

64) Black Holes - A collapsed star that is so dense, and whose gravitational pull is so great, that not even light can escape it. Such stars would look like black holes in a black universe.

Karl Schwarzschild (October 9, 1873 - May 11, 1916) was a German Jewish physicist and astronomer. He is also the father of astrophysicist Martin Schwarzschild.

He was born in Frankfurt am Main. He was something of a child prodigy, having a paper on celestial mechanics published when he was only sixteen. He studied at Strasbourg and Munich, obtaining his doctorate in 1896 for a work on Jules Henri Poincaré's theories.

From 1897, he worked as assistant at the Kuffner Sternwarte (Observatory) in Vienna, where he developed a formula to calculate the optical density of photographic material.

65) Insulin - Insulin is a hormone produced by the pancreas that allows the body to pull sugar from blood and burn it to produce energy.

Frederick Grant Banting KBE MC FRSC (November 14, 1891 – February 21, 1941) was a Canadian medical scientist, doctor and Nobel laureate noted as one of the co-discoverers of insulin.

Banting was born in Alliston, Ontario. After studying medicine at the University of Toronto and graduating in 1916, he served in the Canadian Army Medical Corps during World War I. After the war, he returned to Canada and between 1919 and 1920 completed his training as an orthopedic surgeon at the Hospital for Sick Children in Toronto. From 1920 until 1921 he did part-time teaching in orthopaedics at the University of Western Ontario at London, Ontario, Canada, besides his general practice. Dissatisfied with his practice and fascinated by the idea of alleviating diabetes, Banting left London and moved to Toronto. There, on 17 May 1921 he began his research at the University of Toronto, under the supervision of Professor John Macleod. He was assigned a single assistant to help him, the young graduate student Charles Best.

Fun Facts: In 1922 a 14-year-old boy suffering from type I diabetes was the first person to be treated with insulin. He showed rapid improvement.

66) Neurotransmitters - Chemical substances that transmit nerve impulses between individual neuron fibers.

Otto Loewi (June 3, 1873 – December 25, 1961) was a German pharmacologist whose discovery of acetylcholine helped enhance medical therapy. The discovery earned for him the Nobel Prize in Physiology or Medicine in 1936 which he shared with Sir Henry Dale. He has been referred to as the "Father of Neuroscience."

Fun Facts: The longest nerve cell in your body, the sciatic nerve, runs from your lower spine to your foot, roughly two to three feet in length!

67) Human Evolution - Humanoids evolved first in Africa and, as Darwin had postulated,developed from the family of apes.

Raymond Dart (February 4, 1893 – November 22, 1988) was an Australian anatomist and anthropologist best known for his discovery in 1924 of a fossil of Australopithecus (extinct hominids closely related to humans) at Taung in Northwestern South Africa. The son of a farmer and tradesman, he was married twice and had two children.

He was born in Toowong, Queensland, Australia and studied at Ipswich Grammar School, the University of Queensland, University of Sydney and University College, London, before taking a position as head of the newly established department of anatomy at the University of Witwatersrand in Johannesburg, South Africa in 1922.

Fun Facts: Darwin believed that humanoids emerged in Africa. No one believed him for 50 years, until Dart uncovered his famed skull in 1924.

68) Quantum Theory - A mathematical system that accurately describes the behavior of the subatomic world.

Max Born (December 11, 1882 – January 5, 1970) was a physicist and mathematician who was instrumental in the development of quantum mechanics. He also made contributions to solid-state physics and optics and supervised the work of a number of notable physicists in the 1920s and 30s. Born won the 1954 Nobel Prize in Physics.

Born was born in Breslau , which at Born's birth was in the Prussian Province of Silesia. He was one of two children borne to Gustav Born, (b. April 22, 1850, Kempen, d. July 6, 1900, Breslau), an anatomist and embryologist, and Margarethe Kauffmann (b. January 22, 1856, Tannhausen, d. August 29, 1886, Breslau), from a Silesian family of industrialists. Gustav and Margarethe married on May 7, 1881. Max Born had a sister called Käthe (b. March 5, 1884), and a half-brother called Wolfgang (b. October 21, 1892), from his father's second marriage (m. September 13, 1891) with Bertha Lipstein. His mother died when Max Born was four years old.

Fun Facts: In the bizarre quantum world, many of our “normal” laws do not apply. There, objects (like elec trons) can be (and regularly are) in two different places at once with out up setting any of the laws of quantum existence.

69) Expanding Universe - The universe is expanding. The millions of galaxies move ever outward, away from its center.

Edwin Powell Hubble (November 20, 1889 – September 28, 1953) was an American astronomer. He profoundly changed astronomers' understanding of the nature of the universe by demonstrating the existence of other galaxies besides the Milky Way. He also discovered that the degree of redshift observed in light coming from a galaxy increased in proportion to the distance of that galaxy from the Milky Way. This became known as Hubble's law, and would help establish that the universe is expanding.

Fun Facts: Because the universe is expanding, every galaxy in existence is moving away from our own Milky Way—except for one. Andromeda,our nearest neighbor, is moving on a collision course with the Milky
Way. Don’t worry, though: the collision won’t occur for several million years.

70) Uncertainty Principle - It is impossible to know the position and motion of an elementary particle (e.g., an electron) at the same time.

Werner Heisenberg (5 December 1901 in Würzburg–1 February 1976 in Munich) was a German theoretical physicist. He made contributions to quantum mechanics, nuclear physics, quantum field theory, and particle physics.

Heisenberg, along with Max Born and Pascual Jordan, set forth the matrix formulation of quantum mechanics in 1925. Heisenberg was awarded the 1932 Nobel Prize in Physics.

Fun Facts: Werner’s best subjects were mathematics, physics, and religion, but his record through out his school career was excellent all round.In fact his mathematical abilities were such that in 1917 (when he was 16) he tutored a family friend who was at the university studying calculus.

71) Speed of Light - The speed at which light travels—a universal constant.

Albert Abraham Michelson (December 19, 1852 – May 9, 1931) was a Polish-American physicist known for his work on the measurement of the speed of light and especially for the Michelson-Morley experiment. In 1907 he received the Nobel Prize in Physics. He became the first American to receive the Nobel Prize in sciences.

Michelson, the son of a Polish-Jewish merchant (father) and a Polish mother, was born to a Polish-Jewish family in what is today Strzelno, Poland (then Strelno, Provinz Posen in the Kingdom of Prussia). He moved to the United States with his parents in 1855, when he was two years old. He grew up in the rough mining towns of Murphy's Camp, California and Virginia City, Nevada, where his father was a merchant. He spent his high school years in San Francisco in the home of his aunt, Henriette Levy (née Michelson), who was the mother of author Harriet Lane Levy.

Fun Facts: Traveling at light speed, your ship could go from New York to Los Angeles 70 times in less than one second. In that same one second you could make seven and a half trips around the earth at the equator.

72) Penicillin - The first commercially available antibiotic drug.

Sir Alexander Fleming (6 August 1881 – 11 March 1955) was a Scottish biologist and pharmacologist. Fleming published many articles on bacteriology, immunology, and chemotherapy. His best-known achievements are the discovery of the enzyme lysozyme in 1922 and the discovery of the antibiotic substance penicillin from the fungus Penicillium notatum in 1928, for which he shared the Nobel Prize in Physiology or Medicine in 1945 with Florey and Chain.

Fun Facts: American researchers in Peoria, Illinois, were able to develop commercial production of
penicillin first, because two of penicillin’s favorite foods turned out to be a strain of local Illinois corn and rotting cantaloupes, donated by a Peoria mar ket. Those food bases helped researchers increase their production of penicillin from 400 million to over 650 billion units a month.

73) Antimatter - Anti matter are particles of the same mass and composition as protons and electrons, but with an opposite electrical charge.

Paul Adrien Maurice Dirac was a British theoretical physicist. Dirac made fundamental contributions to the early development of both quantum mechanics and quantum electrodynamics. He held the Lucasian Chair of Mathematics at the University of Cambridge and spent the last ten years of his life at Florida State University. Among other discoveries, he formulated the so-called Dirac equation, which describes the behavior of fermions and which led to the prediction of the existence of antimatter. Dirac shared the Nobel Prize in physics for 1933 with Erwin Schrödinger, "for the discovery of new productive forms of atomic theory."

Fun Facts: When matter converts to energy, some residue is always left.Only part of the matter can be converted into energy. Not so with antimatter. When antimatter collides with matter, 100 per cent of both matter and antimatter are converted into us able energy. A gram of antimatter would carry as much po ten tial energy as 1,000 space shuttle external tanks carry.

74) Neutron - A subatomic particle located in the nucleus of an atom with the mass of a proton but no electrical charge.

Sir James Chadwick, CH (20 October 1891 – 24 July 1974) was an English physicist and Nobel laureate in physics awarded for his discovery of the neutron.

James Chadwick was born in Bollington, Cheshire, the son of John Joseph Chadwick and Anne Mary Knowles. He went to Bollington Cross C of E Primary School, attended Manchester High School, and studied at the Universities of Manchester and Cambridge. In 1913 Chadwick went and worked with Hans Geiger at the Technical University of Berlin. He also worked with Ernest Rutherford. He was in Germany at the start of World War I and would be interned in Ruhleben P.O.W. Camp just outside Berlin. During his internment he had the freedom to set up a laboratory in the stables. With the help of Charles Ellis he worked on the ionization of phosphorus and also on the photo-chemical reaction of carbon monoxide and chlorine. He spent most of the war years in Ruhleben until Geiger's laboratory interceded for his release.

Fun Facts: A neutron has nearly 1,840 times the mass of the electron.How does that size compare with a pro ton?

75) Cell Structure - The first accurate map of the many internal structures that make up a living cell.

Albert Claude (August 24, 1899 – May 22, 1983) was a Belgian biologist who won the Nobel Prize in Physiology or Medicine in 1974. He studied medicine at the University of Liege (Belgium). During the winter of 1928-29 he worked in Berlin, first at the Institut für Krebsforschung, and then at the Kaiser Wilhelm Institute for Biology, Dahlem. In the summer of 1929 he joined the Rockefeller Institute. While working at Rockefeller University in the 1930s and 1940s, he used the electron microscope to make images of cells which deepened the scientific understanding of cellular structure and function. He also developed a method for differential centrifugation, which separates cellular components based on their density.

Fun Facts: There are more than 250 different types of cells in your body.yet they all started as, and grew out of, one single cell—the fertilized egg cell.