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1880 |
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1880 |
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Walther Flemming, Eduard Strasburger, Edouard van
Beneden, and others elucidated the essential facts of
cell division and stressed the importance of the
qualitative and quantitative equality of chromosome
distribution to daughter cells.
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1880-90 |
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1881 |
James A Garfield becomes twentieth president of the United States.
Six months after taking office, Garfield becomes the second US President to be assassinated.
Chester A. Arthur becomes twenty-first president of the United States.
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Eduard Strasburger coins the terms CYTOPLASM and
NUCLEOPLASM.
W. Flemming discovers lampbrush chromosomes and coins the term MITOSIS.
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1882 |
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Pierre Émile Duclaux introduces the custom of
designating an enzyme by the by the name of the substrate
on which its action was first reported and adding the
suffix "- ase".
Edouard van Beneden announced the principles of genetic continuity of chromosomes and reported the occurrence of chromosome reduction at germ cell formation. The sperm and egg are haploid and fertilization restores the diploid chromosome number. Wilhelm Roux offers a possible explanation for the function of mitosis.
A. Weismann points out the distinction in animals between the somatic
cell line and the germ cells, stressing that only changes in germ cells are
transmitted to further generations.
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1883 |
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Walther Flemming, Eduard Strasburger and Edouard van
Beneden demonstrate that chromosome doubling occurs by a
process of longitudinal splitting. Strasburger describes
and names the PROPHASE, METAPHASE,
and ANAPHASEstages of chromosomal division.
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1884 |
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Identification of the cell nucleus as the basis for
inheritance was independently reported by Oscar Hertwig,
Eduard Strasburger, Albrecht von Kölliker, and August
Weismann.
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1884-88 |
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Karl Rabl theorized the individuality of chromosomes in
all stages of the cell cycle.
Walther Flemming observed sister chromatids passing to opposite poles of the cell during mitosis.
August Weismann formulated the germ plasm theory which
held that the germ plasm was separate from the
somatoplasm and was continuous from generation to
generation.
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1885 |
Grover Cleveland becomes twenty-second president of the United States.
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Francis Galton devised a new useful statistical tool, the
correlation table.
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1886 |
Daimler produces his first car.
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August Weismann elaborated an all-encompassing theory of
chromosome behavior during cell division and
fertilization and predicted the occurrence of
a reduction division (meiosis) in all sexual organisms.
Wilhelm Roux put forth the suggestion that the linearly arranged qualities of the chromosomes were equally transmitted to both daughter cells at meiosis.
Edouard van Beneden demonstrated chromosome reduction in
gamete maturation, thereby confirming August Weismann's
predictions.
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1887 |
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Theodor Boveri verifies August Weismann's predictions of
chromosome reduction by direct observation in Ascaris.
Heinrich Wilhelm Gottfried Waldeyer names the CHROMOSOME.
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1888 |
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Francis Galton publishes Natural Inheritance. In it he describes
the quantitative measurement of metric traits in populations. He thus founds
biometry and the statistical study of variation. Ultimately, he formulates the
Law of Ancestral
Inheritance, a statistical description of the relative
contributions to heredity made by one's ancestors.
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1889 |
Benjamin Harrison becomes twenty-third president of the United States.
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1890 |
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