• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

The Progression of Genetics from Gregor Mendel to Polymerase Chain Reaction

Extracts from this document...

Introduction

The Progression of Genetics from Gregor Mendel to Polymerase Chain Reaction Gregor Mendel is often recognised as the "Father of Genetics". An Austrian monk who conducted experiments within the monastery garden to investigate inheritance and variation, Mendel cultivated and tested some 29000 pea plants between 1856 and 1863. His experiments brought forth two generalisations which later became known as Mendel's Laws of Heredity (or Mendelian inheritance). These are described in his paper "Experiments on Plant Hybridisation" and include The Law of Segregation, which explains the concepts of dominant and recessive alleles inherited from each parent, and The Law of Independent Assortment which concluded that different traits are inherited independently of each other. (1) However, the significance of Mendel's work was not realised until around 1900. Before this, in 1869 the Swiss biologist Friedrich Miescher was investigating leukocytes from pus-soaked bandages in order to isolate and study the nucleus. He subjected purified nuclei to an alkaline extraction followed by acidification resulting in a precipitate being formed which Miescher called nuclein, also discovering its composition of nitrogen, phosphorus and sulphur. ...read more.

Middle

Their experiment involved removing various organic compounds from a bacteria cell, if the remaining compounds were still able to cause another strain of bacteria to transform then the substances removed could not be the carrier of genes. Proteases were used to remove proteins, thought to carry genetic instruction, and the other bacteria strain was able to transform - showing that although the protein had been removed - genetic instructions were still present. Therefore, DNA was then removed using a deoxyribonuclease enzyme and it was found the other strain of bacteria did not transform - proving that DNA was the carrier of genes in cells. (6) (7) This work was further proved by Alfred Hershey and 1952 with the Hershey-Chase experiment. Two T2 phages were used, one containing radioactive labelled protein, one containing radioactive labelled DNA, to infect bacteria. The bacteria and phage coat were then separated by blending and centrifugation and the radioactive DNA was found to be transferred to the bacteria, whereas the protein stayed in the phage coat. ...read more.

Conclusion

The workings of DNA were largely understood. (3) This understanding led to the possibility of changing and manipulating DNA, with the discovery of restriction enzymes in bacterium that could be used to "cut and paste" DNA sequences. In 1983 Kary Mullis, an American Biochemist, developed the Polymerase Chain Reaction technique of amplifying small amounts of DNA; although the main principles of PCR were described in 1971 by Kjell Kleppe, a Norwegian scientist. PCR is now used in many genetic techniques requiring the amplification of DNA, including genetic fingerprinting, paternity testing, sequencing, the detection of genetic diseases and the analysis of ancient DNA. Research progressed from the initial aim of understanding to the ways in which knowledge of genetics can be successfully exploited through the second half of the 20th century. This saw the introduction of gene therapy, genetically modified crops, cloning and use of stem cells. (9) Also in the late 20th century the task became to sequence particular genes (for example the gene in which defects cause Cystic Fibrosis) and map the genomes of increasingly complex organisms. The Human Genome Project was completed in 2003. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Genetics, Evolution & Biodiversity section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Genetics, Evolution & Biodiversity essays

  1. Peer reviewed

    An Investigation into the effect of caffeine on reaction times

    5 star(s)

    2.54 19.83 28.70 14.81 6.48 68 65 69 72 71 61 58 -4.41 6.15 4.35 4.41 -10.29 -14.71 LR 110 111 100 108 110 129 116 0.91 -9.09 -1.82 0.00 17.27 5.45 64 72 62 72 71 75 68 12.50 -3.13 12.50 10.94 17.19 6.25 SM 105 112 117 114

  2. Free essay

    Cloning Reasearch Paper

    During the human cloning process, a lot of human embryos are created and tested for viability. Some are either discarded or frozen for future use. First, it is heavily debated if killing a human embryo that is only a few living cells is murdering a person.

  1. case study- cystic fibrosis

    on what people have said about cloning pigs: "All the known technical hurdles [for pig to human transplants] have now been overcome. An end to the chronic organ shortage is now in sight." "What we are talking about is a technique that carries risks for the population at large, as well as the potential to save lives.

  2. Investigate patterns of inheritance for a single characteristic such as body colour of Drosophila ...

    For details of Drosophila Melanogaster please see appendix 1. The trait examined is body colour. Materials and Methods In this cross the characteristic examined was body colour. (See table 1 in Appendix for mutant characteristics of Drosophila) Five wild type males with homozygous genotype were mated with five ebony bodied females, also with homozygous genotype.

  1. Management style, culture & organizational structure.

    This technique can sequence an amazing 12 000 bases per minute. Thousands of genes have been sequenced using these methods and the entire genomes of several organisms have also been sequenced. A huge project is underway to sequence the human genome, and it delivered a draft sequence in June 2000.

  2. Gregor Mendel

    Many other biologists used Mendel's research as a basis for their own and Mendelian genetics is studied and taught throughout the world. Gregor Mendel died in Brunn (Brno) on January 6, 1884. He came up with 5 main theories from his work.

  1. Explain how DNA fingerprinting works.

    Normally females have two X chromosome and males have one X and one Y chromosome. If a female inherits one X chromosome with the mutated FMR-1 gene, she will still have a spare X chromosome with the normal gene. However, if a male inherits an X chromosome with the abnormal

  2. Chromosomes and DNA

    This table shows types of disease which are not caused by a pathogen.DiseaseExampleDegenerative (caused by a breakdown of tissues)Multiple sclerosisDietary (caused by something you eat or something lacking in your diet)ScurvyEnvironmental (caused by a condition in your environment)AsbestosisPhysiological (caused by a body system not working correctly)DiabetesGenetic (inherited)Sickle-cell anaemia, cystic fibrosis,

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work