This website uses cookies to ensure you have the best experience. Learn more

History And Discovery Of Dna Essay

1059 words - 4 pages

DNA is the common name for Deoxyribonucleic acid. This is made up of nucleic acids containing deoxyribose (sugar), consisting of complex molecules, present in the chromosomes of all plant and animal cells, and carrying in coded form instructions for passing on hereditary characteristics.The DNA molecule takes the shape of a double helix, a simple structure that resembles gently twisted ladders. The rails of the ladder are made of pairs of nitrogen-containing nucleotides, which are subdivisions of DNA. Because each nucleotide within a rung of the DNA ladder is always paired with the same complimentary nucleotide, one half of the molecule can serve as a template for the construction of the other half. The four nucleotides in DNA contain the bases adenine (A), guanine (G), cytosine (C) and thymine (T).The people responsible for the discovery of the double-helical structure of DNA were Francis Crick, Rosalind Franklin, Linus Pauling, James Watson and Maurice Wilkins.To solve the structure of DNA four ideas had to come together:•The first was that the phosphate backbone was on the outside, bases on the inside.•That the molecule was a double helix.•That the strands were antiparallel.•That it had a specific base pairing.Erwin ChargaffTo understand the DNA molecule better, scientists were trying to make a model to understand how it works and what it does. In the 1940’s Erwin Chargaff noticed a pattern in the amounts of the four bases: adenine, guanine, cytosine, and thymine. He took samples of DNA of different cells and found that the amount of adenine was almost equal to the amount of thymine, and that the amount of guanine was almost equal to the amount of cytosine. Thus you could say: A=T, and G=C. This discovery later became Chargaff’s Rule.Rosalind Franklin and Maurice WilkinsRosalind Franklin and Maurice Wilkins decided to try to make a crystal of the DNA molecule. If they could get DNA to crystallize, then they could make an x-ray pattern, thus resulting in understanding how DNA works. These two scientists were successful and obtained an x-ray pattern. The pattern appeared to contain rungs, like those on a ladder between two strands that are side by side. It also showed by an “X” shape that DNA had a helix shape.Franklin found out that by bundling super thin strands of DNA and zapping them with a super fine x-ray beam there were two forms of hydration — the A form (easy to photograph) and the B form (hard to photograph). Her B form photographs showed a fuzzy cross, which meant a helix. Since the water would be attracted to the phosphates in the backbone, and the DNA was easily hydrated and dehydrated, she guessed that the backbone was on the outside and the bases were on the inside. The first part of the problem was solved. In May 1952 Franklin got the first good photograph of the B form of DNA. The photograph showed a double helix, which was the second part of the problem that had to be proved. In...

Find Another Essay On History and Discovery of DNA

The pros and cons of DNA profiling

875 words - 4 pages of information to the government without knowing for sure what they might use it for, other than criminal cases, missing persons or things in that nature, would be an invasion of privacy, and also if the system databases are not secure enough, then people could get tremendous information about you just from your DNA, as in medically, and basically information that's in your DNA is in your whole family history, sisters, brothers, mother, father, DNA can trace your family history way back to see who you are related to. I think it should be the publics choice whether or not to give samples of DNA.

Pros and Cons of Recombinant DNA Technology

1490 words - 6 pages Introduction – A historical overview The history of rDNA technology dates back to 1865 when Gregor Mendel, using the pea plant demonstrated and proved some of the basic laws of genetics such as 1) Law of segregation, 2) Law of independent assortment and 3) Law of dominance. Mendel laid the foundation for genetics upon which experiments were conducted in later years. Later in 1915, T.H. Morgan established the fact that chromosome contains genes

Pos. and Neg. of DNA Profiling

966 words - 4 pages The Positives and Negatives on DNA Profiling DNA testing has many uses, both positive and negative, in our society. Genetic profiling has been beneficial in paternity suits and rape cases, where the father or the assailant could be identified. However, despite its growing number of utilizations, DNA profiling is extremely hazardous when results are inaccurate or used to discriminate. Many have benefited from the genetic engineering that has

The Collection and Retention of DNA

2170 words - 9 pages Introduction DNA testing has been the center of attention in many criminal justice cases. The United States corrections centers have utilized the DNA testing process. Seventeen death row inmates have been exonerated by the use of these tests. Earl Washington was convicted of rape and murder in 1984. Although he confessed to the rape, he was also diagnosed as being mentally retarded. In October of 2000 Mr., Washington was given a DNA test

ethical and legal implications of dna databases

2607 words - 11 pages Introduction The concept of DNA testing has expanded throughout the last several decades, and attention needs to be paid to the methods and implications of storing and using the samples. The human genome is a complex structure comprised of billions of base pairs. Only 0.1% of DNA makes up all of the differences in humans’ physical appearance (Pattock, 2011, p.855). Each person has about one hundred trillion cells, all of which contain

Chemistry and the Structure of DNA

690 words - 3 pages Genetics relies on chemistry to explain phenomena related to the field. The structure of DNA relies on chemistry. In fact, when James Watson and Francis Crick discovered the structure of DNA, they did so by building models based on the laws of chemistry. Chemistry also relates heavily to the structure and function of one of the main products of DNA: protein. Chemistry dictates the structure of DNA. DNA is a polymer of monomers called nucleic

The Excavation and Discovery of Tutankhamun's Tomb

1046 words - 5 pages , Eyewitness to History, www.eyewitnesstohistory.com accessed 16/5/14 Saunders J, 2012, Howard Carter and the Tomb of Tutankhamun, History in an hour, http://www.historyinanhour.com/2012/11/04/howard-carter-and-the-tomb-of-tutankhamun/ accessed 16/5/14 Kyffin J, 2013, The discovery of Tutankhamun’s tomb and the legacy of Howard Carter, The Independent, http://blogs.independent.co.uk/2013/02/17/the-discovery-tutankhamuns-tomb-and-the-legacy-of-howard-carter/ accessed 16/5/14 Author Unknown, 2014, Entrance to King Tut’s tomb discovered, History Channel, http://www.history.com/this-day-in-history/entrance-to-king-tuts-tomb-discovered accessed 16/5/14

The Discovery of Radioactivity and its Effects

1189 words - 5 pages radioactivity in chemotherapy to kill the bad cells in a particular part of a persons body. They have a way to aim the radiation where they want it to go then they shoot it to kill the cancer cells before they spread throughout the body. This causes the person to lose hair because there hair cells are being killed by the radiation as well. Radiation and transmitted radioactive waves are harmful. When knowledge is provided about the subject it alleviates the ignorance and allows us to be aware. Through history and the discovery of radiation we are able to prevent the spreading of the effect it has on people. Don’t be dumb. Educate yourself on radioactivity.

The Discovery and Impact of Agriculture

659 words - 3 pages The discovery of agriculture has led to many profound changes in society. From its origin during the Neolithic era, to its evolution throughout modern society, agriculture has formed and shaped human society to what it is today. Without agriculture, society would still be a hunting and gathering community. However, because of the uncovering of agriculture, early humans were able to grow crops and domesticate animals. Moreover, farming has

Insulin: Discovery and Mechanism of Action

1426 words - 6 pages . Web. 19 November 2013. http://www.nobelprize.org/educational/medicine/insulin/diabetes-insulin.html Gower, Timothy. "Discovery Health." Discovery Fit and Health. Discovery Fit and Health, n.d. Web. 18 Nov. 2013. http://health.howstuffworks.com/medicine/medication/history-of-insulin.htm "How Insulin Works." Insulin's Mechanism of Action. N.p., n.d. Web. 19 Nov. 2013. http://www.medbio.info/horn/time%203-4/insulin's%20mechanism%20of%20action.htm

Edward Jenner and the Discovery of Vaccines

1132 words - 5 pages Edward Jenner and the Discovery of Vaccines Edward Jenner (1749-1823) trained in London, under John Hunter, and was an army surgeon for a period of time. After that, he spent his whole career as a country doctor in his home county, Gloucestershire (West of England). His research was based on careful case studies and clinical observation more than a hundred years before scientists could explain what viruses and diseases

Similar Essays

Discovery Of The Structure Of Dna

2524 words - 10 pages discovery of the power the lies within the double helix, but rather the work of many scientists that was carefully picked apart and pieced together by the two who received the most fame for the work. Scientists’ knowledge of DNA was reported as early as 1868, when the Swiss physician Fritz Miescher discovered its presence in the nuclei of cells (Frank-Kamenetskii 10, 1997). Until the study of the structure of DNA led to the discovery of its

How Marie Curie's Discovery Of Radium Transformed Science, Medicine And The Roles Of Women Throughout History

1925 words - 8 pages Marie Curie is the most influential person in history. Her discovery of radium and its uses in science and technology have grown rapidly throughout history, which has contributed to everything from health science to national security. Medical care and airport security would not be as accurate or efficient without X-ray machines and radiotherapy. Marie Curie’s discovery of radium transformed science, medicine, and the roles of women throughout

The History Of The Discovery Of Elements: Periodic Table

702 words - 3 pages This chapter talks about the history of the discovery of elements, the encounters of scientists and the contributions of them to give un what we now know as the periodic table. In this periodic table we able to see a very organized grouping of elements both natural and those produced in labs. Before the periodic table there was no order, method or clarity for the elements being discovered. Some like nitrous oxide were at a point used for

German History: The Discovery Of Otzi, "The Iceman"

1575 words - 6 pages Perhaps the most remarkable discovery of the latter 20th century was that of the iceman, Ötzi. His discovery changed the view of prehistoric life, and gave reason for scientists to rethink the dates of Bronze Age. It is not only remarkable that his body survived for over 5,000 years, but also that his tools and clothing were in such excellent shape. Scientists now know many details about the man known as Ötzi. They know what region he