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Galen of Pergamon describes the human body
Galen was a Greek physician who began studying medicine at the age of 16. He distinguished seven pairs of cranial nerves, described the valves of the heart, and observed the structural differences between arteries and veins. One of his most important demonstrations was that the arteries carry blood, not air.
https://www.britannica.com/biography/Galen-of-Pergamum -
Lamarck develops Hypothesis of evolution by means of acquired characteristics
If an organism changes during life in order to adapt to its environment, those changes are passed on to its offspring. He said change is determined by what the organisms need or want. He believed over time, the “design” of certain animals changed depending on their ways to survive, for example, he believes giraffes developed their long necks over time through generations to be able to reach tall trees.
http://necsi.edu/projects/evolution/lamarck/lamarck/lamarck_lamarck.html -
The Voyage of the HMS Beagle
In the year 1831, Charles Darwin received an invitation: to sail around the world on the HMS Beagle. He claims it was the “most important event of his life” and it was the “starting point of his career”. He was just 22 when he set sail on the HMS Beagle.
https://www.amnh.org/exhibitions/darwin/a-trip-around-the-world/ -
Louis Pasteur refutes spontaneous generation
Previous scientist said it was because living organisms in the air were falling into the broth and making bacteria grow, but other people disagreed and said it was because it was exposed to air. Louis Pasteur decided to make an “s shaped” flask that allowed air through but not living organisms in the air and discovered it was in fact the living organisms in the air that was causing the broth to spoil and grow bacteria.
https://www.youtube.com/watch?v=Z7oLUWDeq7w -
The Origin of species by means of Natural Selection is published
“On the Origin of Species” is a book written by Charles Darwin. It took Darwin 20 years to write and publish. It is the “foundation of evolutionary biology”. By 1872, the book had run through 6 editions.
http://www.history.com/this-day-in-history/origin-of-species-is-published -
Gregor Mendel publishes works on inheritance of traits in pea plants
Gregor Mendel, through his theories and work on pea plants, discovered the fundamental laws of inheritance. The experiments he did on these pea plants took him 8 years. During these experiments, he discovered an organism with alternate forms of a gene will express the form that is dominant.
http://www.dnaftb.org/1/bio.html -
Plasmodium falciparum is described as the causative agent of
Plasmodium falciparum is a unicellular protozoan parasite of humans. It is transmitted through the bite of a female anopheles mosquito. It is responsible for approximately 50% of malaria cases. It causes the disease's most dangerous form called falciparum malaria. It is regarded as the deadliest form to humans.
https://en.wikipedia.org/wiki/Plasmodium_falciparum -
The Germ Theory of Disease is published
The Germ Theory of Disease was “fathered” by Louis Pasteur, he was a French biologist who discovered that germs cause disease. Louis Pasteur also discovered the process of pasteurizing milk, when you kill the germs found in milk.
http://www.bbc.co.uk/schools/gcsebitesize/history/shp/modern/indrevknowledgerev2.shtml -
Hardy and Weinberg independently develop the Hardy-Weinberg equation for determining allele frequencies in populations
The Hardy-Weinberg equation is a mathematical equation to determine the genetic variation of a population. The equation is used to determine genotypes from parents to offspring.
http://www.nature.com/scitable/definition/hardy-weinberg-equation-299 -
T. Hunt Morgan discovers sex-linkage
Thomas Hunt Morgan was looking at a fruit fly through a hand lens when he noticed the fly had white eyes rather than the usual red eyes they normally have. He was interested in how this could have happened. He chose to do a simple breeding analysis to find out more about white eyes. He learned that specific traits are linked with a particular chromosome.
http://www.nature.com/scitable/topicpage/thomas-hunt-morgan-and-sex-linkage-452 -
Neils Bohr develops the Bohr model of atom structure
Neils Bohr develops the Bohr model of atom structure
Bohr created this model of atom structure to showcase how electrons can have stable orbits around the nucleus. The Rutherford model of the atom was a bust because any charged particle moving on a curved path emits electromagnetic radiation and the electrons would lose energy and spiral into the nucleus.
http://abyss.uoregon.edu/~js/glossary/bohr_atom.html -
Frederick Griffith describes the process of transformation
Griffith’s experiment was one of the first to show that bacteria can get DNA through a process called transformation. He used a few different types of a bacteria that effects mice some of the strains of the bacteria were covered in a coating and some were not. On the ones that were covered, the host (mouse) would die, the ones without the coating, the host would kill the bacteria.
https://simple.wikipedia.org/wiki/Griffith%27s_experiment -
Avery, MacLeod and McCarty determine that DNA is the molecule that carries the genetic code
These three scientists believed that DNA is the substance that causes bacterial transformation. During this era, many people believed that it was actually marijuana that served the function of carrying genetic information.
https://en.wikipedia.org/wiki/Avery%E2%80%93MacLeod%E2%80%93McCarty_experiment -
Hershey-Chase experiments are published
The Hershey-Chase experiments, also known as the “Blender Experiments” happened because Alfred Hershey believed that proteins were more likely to be the carriers of genetic information than the DNA molecule. To prove this, Hershey and Martha Chase decided to track the transfer of proteins and DNA between a virus and its host.
https://paulingblog.wordpress.com/2009/08/18/the-hershey-chase-blender-experiments/ -
Rosalind Franklin works with DNA and X-Ray crystallography and develops “Image 51”
Photo 51 is a nickname of an x-ray image of DNA taken by a PhD student named Raymond Gosling that was under the supervision of Rosalind Franklin. It was critical evidence in discovering the structure of DNA. Some believe it is the most important photo ever taken.
http://www.bbc.com/news/health-18041884 -
Watson and Crick propose the double helix model of DNA structure
On the morning of February 28, they determined that the structure of DNA was a double-helix polymer, or a spiral of two DNA strands, each containing a long chain of monomer nucleotides, wound around each other. According to their findings, DNA replicated itself by separating into individual strands, each of which became the template for a new double helix.
http://www.history.com/this-day-in-history/watson-and-crick-discover-chemical-structure-of-dna -
Nirenberg Cracks the Genetic Code
The Nirenberg and Matthaei experiment was a scientific experiment performed on May 15, 1961. The experiment deciphered the first of the 64 triplet codons in the genetic code by using nucleic acid to translate specific amino acids. This experiment showed that RNA controlled the production of specific types of protein.
https://en.wikipedia.org/wiki/Nirenberg_and_Matthaei_experiment -
Endosymbiosis is described by Lynn Margulis
In the late 1960’s, Lynn Margulis studied the structure of cells. She discovered that mitochondria generate the energy required for metabolism. To her, they looked a lot like bacteria. Some even suggested that mitochondria came from bacteria.
https://evolution.berkeley.edu/evolibrary/article/history_24 -
Apollo 11 Lands on the Moon
Neil Armstrong and Buzz Aldrin were the first men to walk on the moon. They launched from Earth on July 16th, 1969 and stepped foot on the moon on July 20th, 1969. They spent 21 hours and 38 minutes on the lunar surface. They returned to Earth on July 24th, 1969.
https://airandspace.si.edu/explore-and-learn/topics/apollo/apollo-program/landing-missions/apollo11-facts.cfm -
Spliceosomes were discovered and described
Phillip Sharp and Richard J. Roberts labs revealed that genes of higher organisms are "split" or present in several distinct segments along the DNA molecule. Sharp and Roberts were awarded the Nobel Prize in Physiology or Medicine in 1993 for their discovery.
https://en.wikipedia.org/wiki/Spliceosome -
The Sanger Technique is developed
The Sanger Technique is also known as Sanger Sequencing is a method of DNA sequencing. It was created by Frederick Sanger in 1977.
https://en.wikipedia.org/wiki/Sanger_sequencing -
Deep sea hydrothermal vents and associated life around them are discovered
Scientists wondered how to temperatures in the deep sea could change so drastically in such short distances. They discovered hydrothermal vents were the culprit of sustaining life within the deep ocean and extreme temperatures. They learned that many new species lived with these vents and were thriving. They describe these hydrothermal vents like hot springs or geysers on the ocean floor.
https://www.nationalgeographic.org/media/deep-sea-hydrothermal-vents/ -
Kary Mullis develops Polymerase Chain Reaction
Kary Mullis invented The Polymerase Chain Reaction while working as a chemist. It enabled scientists to make millions of copies of a scarce sample of DNA. The technique transformed the diagnosis of genetic defects and the detection of the AIDS virus in human cells.
http://siarchives.si.edu/research/videohistory_catalog9577.html -
The Innocence Project is founded
The innocence project is a non-profit organization to help prove innocence of those who are wrongfully convicted of a crime through DNA. The project was founded by Barry Scheck and Peter Neufeld. The Innocence Project has so far led to freeing 351 wrongfully convicted people through DNA testing.
https://en.wikipedia.org/wiki/Innocence_Project -
Dolly the Sheep is cloned
Dolly was the first mammal cloned from an adult cell. Her birth proved that specialized cells could be used to create an exact copy of the animal they came from. Dolly was showcased to the world and the media on February 22, 1997. Dolly died in 2003 due to lung disease and severe arthritis.
http://dolly.roslin.ed.ac.uk/facts/the-life-of-dolly/index.html -
Sahelanthropus tchadensis fossil discovered
Sahelanthropus tchadensis is one of the oldest know species in the human family tree. Scientists only have cranial evidence of these species and are believed to have human-like and ape-like features with a pretty small brain. They lived about 6 – 7 million years ago in Africa.
http://humanorigins.si.edu/evidence/human-fossils/species/sahelanthropus-tchadensis -
Human genome is fully sequenced
A genome is an organism's complete set of DNA. Sequencing means determining the exact order of the base pairs in a segment of DNA. Some sources say our genome was never fully sequenced.
http://science.sciencemag.org/content/291/5507/1304.full -
Richard L Bible is executed
Richard Bible was the murderer of a 9-year-old girl. During his trial in 1990, they used DNA analysis to match the blood on his shirt to her DNA.
http://www.abc15.com/news/crime/death-row-diaries-the-first-use-of-dna-technology-in-an-arizona-murder-case -
CRISPr/CAS 9 is identified and described
CRISPr/CAS9 is a gene-editing technique that can target and modify DNA with accuracy. Scientists are using this new technology to prevent diseases such as hepatitis C in human cells and to defy Mendel’s laws of inheritance.
https://motherboard.vice.com/en_us/article/bmjaav/what-is-crisprcas9-and-why-is-it-suddenly-everywhere
