Pssa science grade 8 test prep practice 233026 large

History of Science and Biology

  • Period: 384 BCE to 322 BCE

    Aristotle describes life with the Scala Naturae

    Aristotle researched that animals and plants are the way they are because of their actions. He believed that that the reason why is the environment influences them to become who they are. Their appearance connects to their survival. http://palaeos.com/systematics/greatchainofbeing/scala_naturae.html
  • 161 BCE

    Galen of Pergamon describes the human body

    This person was a Greek physician who mainly focused on medical theories. He studies the human body and animal body trying the find the similarities and differences between the two.
    https://www.britannica.com/biography/Galen-of-Pergamum
  • Alfred Russel Wallace published ideas of evolutionary processes

    Working with Darwin, they both discovered that after each generation, they continued to change. They became very interested in the idea of natural selection. Wallace did later publish a book that became a best seller. However, one did left the idea while the other continued to research. https://evolution.berkeley.edu/evolibrary/article/history_14
  • Lamarck develops Hypothesis of evolution by means of acquired characteristics

    His main idea was to explain how organisms learn to adapt to their environment including their changes of appearance to better survive. He states that overtime, each new generation is better adapted in both physically and mentally to survive in their environment. As time continues, all living organisms will not be the same from 100 years from now. New changes will occur to force trait changes. http://necsi.edu/projects/evolution/lamarck/lamarck/lamarck_lamarck.html
  • The Voyage of the HMS Beagle

    Darwin was a young college student when he was invited to sail to South America. He later than explored the continent and wrote various observations about the different species, plants, and geology. This was the biggest opportunity of his scientific career which than set him up for a bigger discovery later on. https://www.amnh.org/exhibitions/darwin/a-trip-around-the-world/
  • The Origin of species by means of Natural Selection is published

    The main idea, overall, of this book is how it contains the most important information known about Science.Mainly about evolution which includes the animals, plants and rocks. Darwin began writting the book in 1858 and kept adding on until he was finished. It does seem like a diary of all his research from around the world. This book comes in a set of volumes, all having different information. http://darwin-online.org.uk/EditorialIntroductions/Freeman_OntheOriginofSpecies.html
  • The Germ Theory of Disease is published

    During his time, doctors were stumbled at how germs became a disease. A man by the name of Louis Pasteur discovered the idea. Everyone was stocked and afraid that a small bacteria can turn into a sickness. He also an experiment with milk in which he somehow managed to seal away the bacteria to prevent the milk from spoiling. http://www.bbc.co.uk/schools/gcsebitesize/history/shp/modern/indrevknowledgerev2.shtml
  • Louis Pasteur refutes spontaneous generation

    This scientist's experiment changed the world for the better. Basically, he believed that life can appear anyhow and anything, including air. He used a broth and covered it from going bad which than resulted in staying fresh for one year. This changed the medicine field in which helped save lives in a strange way. https://www.zmescience.com/other/feature-post/louis-pasteur-spontaneous-generation-germ-theory/
  • Gregor Mendel publishes works on inheritance of traits in pea plants

    He stated that we inherit our parents genes which is why we look the way we are. He proved his theory by using pea plants of different colors. This resulted in multiple plants changed and modified because of his hypothesis. He also did realize that whatever is inherited will continue on to the next generation of plants which connects to humans today. This experiment took him eight years to complete. http://www.dnaftb.org/1/bio.html
  • The Challenger Oceanography Expedition sails around the world

    This object has done one of the most important history moment in the world. It has discovered the ideas and topics for oceans life and structure.
    https://paleonerdish.wordpress.com/2013/07/01/the-challenger-expedition-and-the-beginning-of-oceanography/
  • Plasmodium falciparum is described as the causative agent of malaria

    This is a disease that was to only be grown in monkeys. However mosquitoes began to carry it and soon spread to people. For people, this can be a heavy inflection especially in the liver. It is possible for it to run in a family tree but more likely to be carried in animals.
    http://cmr.asm.org/content/20/4/579.full
  • Hardy and Weinberg independently develop the Hardy-Weinberg equation for determining allele frequencies in populations

    This mainly explains the idea of evolution through math which refers back to genotype and genetics. Affecting one generation to the next to be a mixture of different crossings from your family. Without this idea, evolution would not occur.
    https://www2.palomar.edu/anthro/synthetic/synth_2.htm
  • T. Hunt Morgan discovers sex-linkage

    His curiosity started when a fruit looked strange. He noticed that the fruit fly had white eyes and he decided to explore the reason why. He figured out that the reason why was because of the hybrid traits among the genetic family.
    https://www.nature.com/scitable/topicpage/thomas-hunt-morgan-and-sex-linkage-452
  • Neils Bohr develops the Bohr model of atom structure

    At a very young age, the scientist had a love for physics. He discovered the atomic structure of an atom which than gave him a nobel prize. This is one of the biggest scientific discovery in history.
    https://www.livescience.com/32016-niels-bohr-atomic-theory.html
  • Frederick Griffith describes the process of transformation

    His experiment used to mouses with different types of bacteria. This resulted in one mouse dying and the other one being okay due to their immune system. The purpose of this experiment was to prove that certain bacteria can be kill off by the immune system.
    https://biologywise.com/frederick-griffiths-experiment-concept-of-transformation
  • Theodosius Dobzhansky publishes Genetics and the Origin of Species

    He explained that evolution and genetics were connected in two ways. He experimented, researched and wrote trying to explain how genetics were connected to life. He even talked about Darwin in his writing saying that his theory could be involved with his. http://www.pnas.org/content/94/15/7691
  • The first atomic bomb is used in war

    A German scientist was the first to create an atomic bomb. He used lots of energy release, and splitting light atoms. This was a huge deal during World War II.
  • Beadle and Tatum publish the 1 gene-1 enzyme hypothesis

    The main purpose of this experiment was to test the idea of enzymes at work due to genes. They experimented with fruit flies and mutated them. This than helped theorize that genes creating enzymes help control balance of what part of the body belong where.
    https://embryo.asu.edu/pages/george-w-beadles-one-gene-one-enzyme-hypothesis
  • Jacques Cousteau develops SCUBA

    This inventor helped changed the way of ocean exploring. He created a scuba suit that helped contain air longer. This meant longer exploration and new discoveries in the ocean. http://www2.padi.com/blog/2014/01/27/jacques-cousteau-the-father-of-scuba-diving/
  • Hershey-Chase experiments are published

    This is a belief that somehow proteins and DNA were connected. They show their evidence through long research and experiments.They used multiple ways to try and prove how proteins and DNA were involved in the genetic coding. https://paulingblog.wordpress.com/2009/08/18/the-hershey-chase-blender-experiments/
  • Avery, MacLoed and McCarty determine that DNA is the molecule that carries the genetic code

    In this time frame, these scientists discovered that there were genetics in DNA. They all changed the way of perspective involving DNA information. Continuing they changed the way of science forever that still influences the world today. https://www.sciencedirect.com/science/article/pii/S0960982213015157
  • Meselson and Stahl work with DNA replication

    This event occurred after the discovery of the double helix. The purpose of this is the idea of separation during the DNA replication. Predicting the model was a huge discovery because of finding that old strands of DNA is involved.
    https://www.nature.com/scitable/topicpage/semi-conservative-dna-replication-meselson-and-stahl-421
  • Period: to

    Watson and Crick propose the double helix model of DNA structure

    Both scientists discovered the structure of DNA, explaining that the DNA has a structure of a double helix. They did understand that genetics had to be involved in the DNA structure but were not sure how or why. This than was a break through and helped with other discoveries. https://profiles.nlm.nih.gov/SC/Views/Exhibit/narrative/doublehelix.html
  • Rosalind Franklin works with DNA and X-Ray crystallography and develops “Image 51”

    During this time frame, Franklin discovered how the X-ray gave off different patterns. She investigated that this was the main reason why the double helix is a double helix. Although during her research it gave off radiation which results in obtaining cancer at a young age and dying before being applauded for her work. https://www.dnalc.org/view/15014-Franklin-s-X-ray-diffraction-explanation-of-x-ray-pattern-.html
  • Miller-Urey experiments published

    This experiment was important to the world of science due to how it was performed and for what reason. Miller did this experiment to prove that apparatuses were involved in trying to simulate the earth. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4089479/
  • Endosymbiosis is described by Lynn Margulis

    This is the idea of mutation involving survival of the fittest and natural selection that adapts to the idea of environmental change influences. She argued that new genes were replaced with old genes due to natural selection and environmental adaption.
    https://evolution.berkeley.edu/evolibrary/article/history_24
  • Nirenberg cracks the genetic code

    This is the idea of how the genetic code became readable. The article goes in more detail of how they used a small experiment to use the protein for cracking the genetic code.
    https://www.nobelprize.org/educational/medicine/gene-code/history.html
  • 4. Apollo 11 lands on the moon

    As leaving the earth and landing on the moon made headline and history. Apollo 11 was when America first landed on the moon and walked without gravity. This was a huge deal as for being in space for the first time.
    https://www.space.com/16758-apollo-11-first-moon-landing.html
  • Theodosius Dobzhansky publishes “Nothing in Science Makes Sense Except in the Light of Evolution.”

    Dobzhansky challenged Darwin's theory about evolution. He notices that the evidence that he found was a little confusing, stating that Darwin's research is not right. He only agrees with one topic of his which is the Light evolution. Religion does seem to be a big part of this concept. Other than that, the rest seems to be a blur. https://answersingenesis.org/theory-of-evolution/nothing-in-biology-makes-sense-except-in-the-light-of-evolution-myth-evalutation/
  • Australopithicus afarensis nicknamed “lucy” fossil discovered

    This skeleton was a major break through for evolution. The discovery was in Africa and was most likely an ape. They did concluded that the creature walked on two feet but showed evidence that she climbed trees.
    https://australianmuseum.net.au/australopithecus-afarensis
  • Ensatina described as a ring species

    This article explains how the creatures were changed through their environment. They adapted to their surroundings more and more after each new generations. Their appearance began to changed in color due to blending in with the surroundings and surviving. https://evolution.berkeley.edu/evolibrary/article/0_0_0/devitt_02
  • Spliceosomes were discovered and described

    During this time, they were using off of what the scientists already knew which was the DNA replication. While researching, they saw how and what cells exactly do this function. https://www.nature.com/scitable/topicpage/rna-splicing-introns-exons-and-spliceosome-12375
  • The Sanger Technique is developed

    This idea is about how different products do multiple jobs for one idea which is DNA replication. This helps create a clear picture for people who are confused.
    https://www.sciencedirect.com/topics/neuroscience/sanger-sequencing
  • Deep sea hydrothermal vents and associated life around them are discovered

    The idea came from trying to answer the question of what is life. During this time, they founded out that there was much more going on in the ocean. For example ridges and high temperature was the biggest discovery.
    https://www.chemistryworld.com/feature/hydrothermal-vents-and-the-origins-of-life/3007088.article
  • Barbara McClintock describes transposons

    She discovered that by using strange phenotype, the result of genetics would have a different outcome. She experimented this and found out that chromosomes had a breakage.
    https://www.nature.com/scitable/topicpage/barbara-mcclintock-and-the-discovery-of-jumping-34083
  • Kary Mullis develops Polymerase Chain Reaction

    This topic is about the discovery about the polymer chain reaction. He noticed that genetics were involved and played a role. The idea was rather new and people soon learned to accept the idea.
    https://www.dnalc.org/view/16065-Kary-Mullis-.html
  • Richard L Bible is executed

    This how Bible got caught with murder and sexual assault. One day a little girl was riding her bike when she never came home. Bible left his DNA on the littler girl when he was found. Once he was found, he was convicted of murder and assault which resulted in his execution in 2011.
    http://www.clarkprosecutor.org/html/death/US/bible1259.htm
  • Human genome is fully sequenced

    As the world of discoveries continue, the process of sequencing relates to the importance of DNA. The meaning is that they are all the genetics in a single DNA structure. https://www.genome.gov/11006943/human-genome-project-completion-frequently-asked-questions/
  • Tommie Lee Andrews is convicted of rape

    This is the story of how a man was convicted by DNA found. The story goes of how he broke into a woman's house where he raped and stabbed her. Luckily he was caught and justice was served through DNA findings in blood.
    https://www.nytimes.com/1988/02/06/us/rapist-convicted-on-dna-match.html
  • Reproductive isolation as a consequence of adaptive divergence in Drosophila pseudoobscrura” published

    Mainly discusses the difference why mating is hard. Each of the gender is different which can cause a tragic outcome involving not being able to mate properly. The article goes more into detail about why the organisms have difficultly mating, especially for females. While explaining the results, they found out that behavior may be involved in mating. But are still unsure to why they act in such a way. https://pdfs.semanticscholar.org/ce90/5c5619a4f5e807eb8b5a595c7344f48b6687.pdf
  • The Innocence Project is founded

    This topic mainly talks about how they can use DNA to prove the wrong doings of bad behavioral people. Which than helps bring justice to the person being the victim.
    https://www.innocenceproject.org/about/
  • Dolly the sheep is cloned

    Dolly is the first mammal to be cloned from a adult cell. She lived for about 6 years even though she could have lived longer. She developed a joint disease that cause her life. This was part of a research to prove the transfer of genes.
    http://www.animalresearch.info/en/medical-advances/timeline/cloning-dolly-the-sheep/
  • Sahelanthropus tchadensis fossil discovered

    This article states that this animals live long ago. They mainly talk about her discovery and how us humans are somehow related to the creature. The use evidence such as how it walked like us so it could be a long ago ancestor of how we evolved. http://humanorigins.si.edu/evidence/human-fossils/species/sahelanthropus-tchadensis
  • CRISPr/CAS 9 is identified and described

    This is a function that helps genes regulate and be immune for bacterial organisms. Different types of these help do different things and have different functions.
    https://www.neb.com/tools-and-resources/feature-articles/crispr-cas9-and-targeted-genome-editing-a-new-era-in-molecular-biology
  • Homo denisova fossil discovered

    This discovery is mainly about how this is connected to a previous human being or ancestor. They believe that this is from a different specie of human because of the structure of the tooth. Resulting to the conclusion that this human was not the only one to appear this way, there were several unique humans that had this structure. https://www.wired.com/2010/12/denisovans/