الموضوع: دراسة احصائية عن اليتم والشخصيات الخالدة
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قديم 08-05-2010, 10:01 PM
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الصورة الرمزية ايوب صابر
ايوب صابر
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افتراضي رد: دراسة احصائية عن اليتم والشخصيات الخالدة
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مندل

غريغور يوهان مندل (Gregor Johann Mendel) (ولد 20 يوليو 1822 - 6 يناير 1884 م) هو أبو علم الوراثة ، وعالم نبات وراهب نمساوي أجرى الكثير من التجارب واكتشف القوانين الأساسية للوراثة. أدت تجاربه في تكاثر نبات البازلاء إلى تطور علم الوراثة وكانت تجاربه هي الأساس لعلم الوراثة الذي يشهد تقدماً في عالم اليوم.

ولد غريغور يوهان مندل ، في بلدة هينزندورف بالنمسا. كان والداه مزارعين فقيرين، وكان مندل طالباً فاشلاً بالدراسة، وتقدم مرتين لامتحان يؤهله لتدريس الثانوية لكنه فشل. ولما كان كثير من المدرسين آنذاك كهنة، دخل مندل عام 1843م دير القديس توماس في برون بالنمسا -(برنو الآن في تشيكيا)- وعمره في ذلك الوقت كان 21 عاماً، وأصبح قسيساً في سلكخرخرائي.
كان الدير في ذلك الوقت ، مركزاً علمياً بالإضافة إلى كونه مركزاً دينياً؛ فالتقى مندل بالعديد من العلماء البارزين هناك. وفي عام 1851م، ابتعثه الدير لدراسة العلوم والرياضيات في جامعة فيينا الشهيرة.

في عام 1853م وعاد إلى الدير، ودرّس علم الأحياء والفيزياء في مدرسة عليا محلية لمدة 14 سنة. وجاءت شهرة مندل العالمية من بحوثه الصغيرة في حديقة الدير على نباتات البازلاء وزهورها وبذورها.
انتخب مندل عام 1868م رئيساً للدير. ومنذ ذلك الحين قيدت مسؤولياته الإدارية من فرصة في الاستمرار في المزيد من البحوث قدماً.




http://ar.wikipedia.org/wiki/%D8%BA%D8%B1%D9%8A%D 8%BA%D9%88%D8%B1_%D9 %8A%D9%88%D9%87%D8%A 7%D9%86_%D9%85%D9%86 %D8%AF%D9%84

Mendel was born into an ethnic German family in Heinzendorf bei Odrau, Austrian Silesia, Austrian Empire (now Hynčice, Czech Republic), and was baptized two days later. He was the son of Anton and Rosine Mendel, and had one older sister and one younger. They lived and worked on a farm which had been owned by the Mendel family for at least 130 years.[3] During his childhood, Mendel worked as a gardener, studied beekeeping, and as a young man attended the Philosophical Institute in Olomouc in 1840–1843. Upon recommendation of his physics teacher Friedrich Franz, he entered the Augustinian Abbey of St Thomas in Brno in 1843. Born Johann Mendel, he took the name Gregor upon entering monastic life. In 1851 he was sent to the University of Vienna to study, returning to his abbey in 1853 as a teacher, principally of physics.
Gregor Mendel, who is known as the "father of modern genetics", was inspired by both his professors at university and his colleagues at the monastery to study variation in plants, and he conducted his study in the monastery's garden. Between 1856 and 1863 Mendel cultivated and tested some 29,000 pea plants (i.e., Pisum sativum). This study showed that one in four pea plants had purebred recessive alleles, two out of four were hybrid and one out of four were purebred dominant. His experiments brought forth two generalizations, the Law of Segregation and the Law of Independent Assortment, which later became known as Mendel's Laws of Inheritance.
Mendel did read his paper, Experiments on Plant Hybridization, at two meetings of the Natural History Society of Brünn in Moravia in 1865. When Mendel's paper was published in 1866 in Proceedings of the Natural History Society of Brünn,[4] it had little impact and was cited about three times over the next thirty-five years. (Notably, Charles Darwin was unaware of Mendel's paper, according to Jacob Bronowski's The Ascent of Man.) His paper was criticized at the time, but is now considered a seminal work.
After Mendel completed his work with peas, he turned to experimenting with honeybees, in order to extend his work to animals. He produced a hybrid strain (so vicious they were destroyed), but failed to generate a clear picture of their heredity because of the difficulties in controlling mating behaviours of queen bees. He also described novel plant species, and these are denoted with the botanical author abbreviation "Mendel".
Elevated as abbot in 1868, his scientific work largely ended as Mendel became consumed with his increased administrative responsibilities, especially a dispute with the civil government over their attempt to impose special taxes on religious institutions.[5] At first Mendel's work was rejected, and it was not widely accepted until after he died. At that time most biologists held the idea of blending inheritance, and Charles Darwin's efforts to explain inheritance through a theory of pangenesis were unsuccessful. Mendel's ideas were rediscovered in the early twentieth century, and in the 1930s and 1940s the modern synthesis combined Mendelian genetics with Darwin's theory of natural selection.
Mendel died on January 6, 1884, at age 61, in Brno, Moravia, Austria-Hungary (now Czech Republic), from chronic nephritis. Czech composer Leoš Janáček played the organ at his funeral. After his death the succeeding abbot burned all papers in Mendel's collection, to mark an end to the disputes over taxation
http://en.wikipedia.org/wiki/Gregor_Mendel


http://www.zephyrus.co.uk/gregormendel.html

http://astro4.ast.vill.edu/mendel/gregor.htm

he was subject to periodic bouts of psychosomatic illens that would keep him in bed for weeks at a time.

http://media.wiley.com/product_data/...047141431X.pdf


- طفولته مجهولة لكن هناك اجماع انه ابن عائلة فلاحين فقيرة.
- يبدو انه كان مصاب بمرض نفسي سيكوسوماتى psychosomatic illens يقعده في السرير لاسابيع في كل مره .
- موقع اخر يقول انه الابن الوحيد لابيه.
- دخل الدير في سن 20 سنه.
- لم يتم التعرف على اهمية ابحاثه الا بعد موته بسنوات.
- الاغلب انه يتيم في سن متأخره.

مجهول