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Barbara McClintock In her early age as being a scientist

Barbara McClintock

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  • birthdate: (1902-06-16)June 16, 1902
  • birthplace: Hartford, Connecticut
  • deathdate: September 2, 1992(1992-09-02) (aged 90) Huntington, New York, US

Her Life as Young Barbara

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Barbara McClintock was an American scientist and geneticist and she was awarded the Nobel Prize in Physiology. She received her PhD in botany. Botany is the study of plants, physiology, structure, genetics and more. She attended Cornell University in 1927. She studied chromosomes and thei breakage size and how these chromosomes could change position. she discovered that genes could be mobile too. She was known as the Jumping Gene Women.[1]

Her Discoveries that made her famous

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Jumping genes are DNA Sequence or transposable element (TE or transposon) is a DNA sequence that can change its position within a genome, this can cause a mutations and changing the cell's genome size. Transposition often results in duplication of the transposable element. Barbara McClintock's discovery of these jumping genes earned her a Nobel Prize in 1983.<ref>{{cite journal |last=McClintock |first=Barbara.[2]

McClintock is best known for her great discovery of the transposable elements, to help her discover this she did an experiment called maize. Maize is corn that is grown widely throughout the world in a lot of different environments. double fertilization, played a big role in this observation experiment. Double Fertilization is when, one sperm fuses with the egg cell's nucleus, and this produces a diploid zygote that will develop into a new plant. the other sperm fuses with the two polar nuclei to form a triploid endosperm, which forms an another layer the process. [3]

Jumping Genes

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Jumping genes are also known as Transposable elements (TEs). The name transposable has the same meaning as jumping gene, it simply means a genetic elements that moves to a different location withing the genome it is in. A lot of these transposables become inactive and no longer have energy to move. Transposables were first discovered in corn during the 1940's and 50's. There were about three different transposons that were discovered by Barbara McClintock. The different classes included II transposons, miniature inverted-repeated transposable elements (MITEs or class III transposons,) and retrotransposons (class I transposons).[4]

Maize Experiment

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Barbara McClintock was the first scientist to figure out that transposable elements, were mobile pieces of genetic material. This DNA she studied was performed in corn, and she observed her studies off of the different seed colors of the corn in each different generation. She dotted down the physical appearance of the corn and she discuss the morphology of the corn seed before the experiment. McClintock discovered these elements by analyzing genetic stocks of corn that were phenotypically unstable[5] She studied the different alleles that lead to the different color change in corn, she figured out that the dominant allele had more affect to the corn more than the recessive alleles. This great discover went global and she was recognized in a Nobel prize sitting and won some rewards during her life time.

Her work during her career

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A lot of characteristics of organisms are determined by heredity. [6] Barbara studied corn's hereditary characteristics, for example she observed the different color of seeds that grew on the corn stalks. She studied how the different kernel colors were passed down through different generations and linked this to a changes in the plants' chromosomes. [7] She proved that genetic elements can change positions and become active or inactive to nearby genes.

Honors and Rewards

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She earned some Nobel Prizes during her lifetime. In 1983 she won two Nobel Prizes in physiology or medicine for her discovery of transposonables or another named this process is called "JUMPING GENES". Mcclintocks's work on transposable elements in genetics led to the idea that the genome of a organism is not stationary [8]

End of her Life time

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McClintock spent her end of her life living up to the Nobel prizes she won, and she was a key leader and a researcher at cold spring harbor on long island, new york laboratory where she furthered her studies. Her death date was September 2 1992, she was 90 years old. she died of natural causes, she never was married and had kids. She also siblings , she was one of four. Her parents names were Thomas Henry McClintock and Sara Handy McClintock. Before her death Barbara was recognized throughout her career as one of the most distingusihed scientist of the 20th centruy. [9]

  1. ^ "Education & Resources - National Women's History Museum - NWHM". www.nwhm.org. Retrieved 2016-11-15.
  2. ^ "Transposons | Learn Science at Scitable". www.nature.com. Retrieved 2016-11-15.
  3. ^ Pray and Zhaurova, Leslie and Kira (copyright 2008). "Barbara McClintock and the Discovery of Jumping Genes (Transposons)". Scitable Mobile (A learning Space for Science). Nature Education. Retrieved Nov 14 2016. {{cite web}}: Check date values in: |access-date= and |date= (help)
  4. ^ "transposon | genetics". Encyclopedia Britannica. Retrieved 2016-12-09.
  5. ^ "McClintock and the Ac/Ds Transposable Elements of Corn". www.ndsu.edu. Retrieved 2016-12-09.
  6. ^ "Barbara McClintock - Facts". www.nobelprize.org. Retrieved 2016-12-09.
  7. ^ "Barbara McClintock - Facts". www.nobelprize.org. Retrieved 2016-12-09.
  8. ^ "Barbara McClintock, 1983 Winner of Nobel Prize in Physiology or Medicine". www.findingdulcinea.com. Retrieved 2016-12-09.
  9. ^ "The Barbara McClintock Papers: Biographical Information". profiles.nlm.nih.gov. Retrieved 2016-12-09.