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161 BCE
Galen of Pergamon describes the human body
He discovered blood in the human arteries and dissection of the human cranial nerves, the nerves that supply key areas of the head, face, and upper chest.
https://www.medicinenet.com/script/main/art.asp?articlekey=1889 -
Lamark develops hypothesis of evolution by means of acquired characteristics
His theory was if an organism changes during life in order to adapt to its environment, those changes are passed onto the offspring. He used animals like elephants and giraffes to prove they have changed and evolved over the years to adapt to what they need such as long trunks and taller necks. http://necsi.edu/projects/evolution/lamarck/lamarck/lamarck_lamarck.html -
The Voyage of HMS Beagle
On this voyage Darwin discovered that our lands rise above sea level which means our continents are rising and our ocean floors are sinking. He came across a band of shells across a cliff that had been 45 feet above sea level which leas him to question if that part of the cliff had been under the ocean some point in time. https://www.aboutdarwin.com/voyage/voyage03.html -
Louis Pasteur refutes spontaneous generation
In this experiment Pasteur added a nutrient broth, bent the necks of the flasks into S shapes, then boiled the broth to kill any microbes. Which refuted the notion of spontaneous generation.
http://www.pasteurbrewing.com/louis-pasteur-experiment-refute-spontaneous-generation/ -
The Origin of Species by means of Natural Selection
Charles Darwins famous selling book Natural Selection was published and was a huge significance in scientific history. This is because his book is now the foundation of botany, cellular biology, and genetics. It was about Evolution and how man and ape could be genetically similar because of our ancestors. http://www.history.com/this-day-in-history/origin-of-species-is-published -
The Germ Theory of Disease is published
Louis Pasteur a French microbiologist published The Germ Theory of Disease in 1894. He discovered that germs cause disease. One of his experiments that leas to this discovery was the pasteurization of milk which prevented it from going sour by killing the germs and sealing it so no ai was exposed. http://www.bbc.co.uk/schools/gcsebitesize/history/shp/modern/indrevknowledgerev2.shtml -
Plasmodium Falciparum is described as causative agent of malaria
Plasmodium Falciparum is a unicellular protozan parasite of humans. It is the deadliest species of Plasmodium that causes Malaria in humans. Humans usually become infected with Plasmodium species that normally infect animals, such as P. Knowlesi. http://www.who.int/ith/diseases/malaria/en/ -
Hardy and Weinberg independently develop the Hardy-Weinberg equation for determining allele frequencies in populations
The equation (p^2+2pq+q^2=1) p is defined as the frequency of the recessive allele for the trait controlled by a pair of alleles (A and a). They concluded Gene pool frequencies are inherently stable but that evolution should be expected in all populations virtually all of the time. https://www2.palomar.edu/anthro/synthetic/synth_2.htm -
T. Hunt Morgan discovers sex-linkage
He studied the genetic change of fruit flies. One day he noticed a male fruit fly had white eyes instead of red eyes. Then did a simple breeding analysis to find out more about white eyes. In doing so he confirmed the chromosome theory. https://www.nature.com/scitable/topicpage/thomas-hunt-morgan-and-sex-linkage-452 -
Neils Bohr develops the Bohr model of Atom Structure
Neils Bohr proposed a theory for the hydrogen atom based on the quantum theory that energy is transferred only in certain well defined quantities. The model depicts the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus. https://www.nobelprize.org/nobel_prizes/physics/laureates/1922/bohr-facts.html -
Fredrick Griffith describes the process of transformation
Fredrick'a experiment showed us that bacteria can distinctly change their function and form through transformation. Transformation is the process which describes one thing changing into another. Before his experiment scientists believed that bacteria that won't respond to medicines we currently have and use. https://study.com/academy/lesson/frederick-griffith-experiment-discovery-quiz.html -
Gregor Mendel publishes works on inheritable of traits in pea plants
Mendel through his experiments and research on pea plants lead to the discovery of fundamental las of inheritance. Which means that genes come in pairs and are inherited as distinct units, one from each parent. Laws are: The Law of Segregation, The Law of Independent Assortment, and The Law of Assortment. http://www.dnaftb.org/1/bio.html -
Avery, Macloed, and McCarty determine that DNA is the molecule that carries the genetic code
Avery, Macloed, and McCarty discovered DNA while studying streptococcus pneumoniae, which is a bacteria that causes Pneumonia. Avery and McCarty observed that proteases and lipases did not destroy the transforming principle. It was rich in RNA and was rich in nucleic acids and high in molecular weight. They isolated DNA.
https://www.genome.gov/25520250/online-education-kit-1944-dna-is-transforming-principle/ -
Rosalind Franklin works with DNA and X-Ray crystallography and develops "image 51"
Raymond Gosling took an image nicknamed "image 51". It was an X-Ray diffraction image of DNA that was found under the supervision of Rosalind Franklin. This was a big deal because it was evidence when scientist were trying to identify the structure of DNA. Rosalind was an expert in X-Ray crystallography and when DNA was crystallized she could see it's structure. https://www.khanacademy.org/science/biology/dna-as-the-genetic-material/dna-discovery-and-structure/a/discovery-of-the-structure-of-dna -
Hershey-Chase experiments are published
Alfred Hershey and Martha Chase has discovered viral DNA enters the bacterial cell during infection and viral protein does not enter bacteria cell during infection so DNA must be the viral genetic material. They tracked the transfer of proteins and DNA between a virus and its host. https://mcb.berkeley.edu/courses/mcb165/HersheyChase.pdf -
Watson and Crick propose the double helix model of DNA structure
In April of 1953 James Watson and Francis Crick presented the new structure of DNA-helix, a molecule that carries genetic information from one generation to the next. They used the phosphate backbone was on the outside with bases on the inside and also a double helix to conclude that DNA was the configuration. https://www.nobelprize.org/educational/medicine/dna_double_helix/readmore.html -
Nirenberg cracks the genetic code
He discovered the first "triplet" a sequence of 3 bases of DNA that codes for one of the twenty amino acids that serve as the building blocks of proteins. http://www.genomenewsnetwork.org/resources/timeline/1961_Nirenberg.php -
Endosymbiosis is described by Lynn Margulis
The theory maintains that ancestors of Eukaryotic cells were "symbiotic consortions" of prokaryotic cells with at least one and possibly more species (endosymbiosis) involved. Lynn Margulis book has influenced biology by giving a plausible explanation foe the explanation for the evolution of eukaryotes. https://www.biology.iupui.edu/biocourses/N100/2k2endosymb.html -
Apollo 11 lands on the Moon
Armstrong and Aldrin and Collins make the missions to be the first humans to step foot on the moon. Leaving behind the American flag they were on the moon for about 2.5 hours collecting samples and data for us to examine and expand our knowledge about the moon and space. https://www.nasa.gov/mission_pages/apollo/apollo11.html -
Deep Sea Hydrothermal Vents and associated life around them are discovered
They were discovered while exploring on an oceanic spreading ridge near the Galapagos Islands. Along with finding the hydrothermal vents were surrounded by large numbers of organisms that had never been seen before. They are the result of sea water percolating down through fissures on the ocean crust in the vicinity of subduction zones.
https://oceanservice.noaa.gov/facts/vents.html -
The Sanger Technique is developed
Sanger sequencing also known as the chain termination method, is a technique for DNA sequencing based upon the selective incorporation of chain-terminating dideoxynucleotides by DNA polymerase during in vitro DNA replication. It was developed by Frederick Sanger in 1977. https://www.sciencedirect.com/topics/neuroscience/sanger-sequencing -
Spliceosomes were discovered and described
Phillip A. Sharp discovered splicing in 1977. Spliceosome is a cellular machine that does some shrinking if mRNA. As the cell transcribes your DNA's nucleic acid sequence into RNA, the spliceosome lands on the newly forming mRNA strand where it chops out unnecessary pieces call introns, and joins together the leftover essential, called exons. Then mRNA is exported to cells cytoplasm, where it gets translated into protein. https://cen.acs.org/articles/93/i39/Uncovering-Spliceosomes-Secrets.html -
Kary Mullis develops Polymerse Chain Reaction
PCR technique invented in 1985 by Kary Mullis allowed scientists to make millions of copies of a scarce sample of DNA. It enhanced many aspects of research involving the genetic defects of humans and AIDS. It also has helped criminologists to link samples of DNA to specific victims. http://siarchives.si.edu/research/videohistory_catalog9577.html -
The Innocence Project is founded
The Innocence project is a non-profit legal organization that it committed to exonerating wrongly convicted people through the use of DNA testing and to reforming the criminal justice system to prevent future injustice. It was founded by Barry Scheck and Peter Neufeld.
https://www.innocenceproject.org/about/ -
Dolly the sheep is cloned
Dolly was apart of a series of experiments at the Roslin institute that were trying to develop a better method for producing genetically modified livestock. Dolly was cloned by an egg cell from a Scottish Blackface sheep and and sperm cell from and Finn Dorset sheep. Because of her white face she was then classified as a clone. http://dolly.roslin.ed.ac.uk/facts/the-life-of-dolly/index.html -
Sahelanthropus techadensis fossil discovered
The Sahelanthropus technadensis is one of the oldest species that has been discovered in scientific history. It was an ape like creature that existed up to 7 million years ago. They were discovered in West-Central Africa. Scientist believed that they walked upright similar to humans. The fossils that were found first was the cranium. http://humanorigins.si.edu/evidence/human-fossils/species/sahelanthropus-tchadensis -
Human genome is fully sequenced
A genome is an organisms complete set of DNA, the DNA molecules are made of twisted strands in which we now call a double helix. It took multiple test subjects blood and DNA to discover the DNA contains Adenine, Thymine, Guanine, and Cytosine. Sequencing is determining the exact order of base pairs in a segment of DNA. When a genome is complete the creation of physical/genetic maps appear clear
https://www.genome.gov/11006943/human-genome-project-completion-frequently-asked-questions/ -
Meselson and Stahl work with DNA replication
Meselson and Stahl had problem, Watson and Crick's double helix seemed to suggest that the two dissociated, each giving rise to a need, complementary strand. The two daughter molecules would thus contain one strand from the parent molecule and replicates. http://www.pnas.org/content/101/52/17895.long -
Richard L. Bible is executed
Richard was teh 25th murderer executed in U.S. in 2011. He was caught with the DNA of the blood of his victim, Jennifer on his shirt connecting her case. It was indeed her blood and he was convicted. http://www.clarkprosecutor.org/html/death/US/bible1259.htm -
CRISPr/CAS9 is identified and described
CRISPr/CAS9 is a genome editing tool that is a faster, cheaper, and more accurate than previous techniques of editing DNA and has a wide range of potential applications. It is a unique technology that enables geneticist and medical researchers to edit parts of the genome by removing, adding; and altering sections of the DNA sequence.
https://www.broadinstitute.org/what-broad/areas-focus/project-spotlight/questions-and-answers-about-crispr
