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  2. Cell theory - Wikipedia

    en.wikipedia.org/wiki/Cell_theory

    He also found for the first time the sperm cells of animals and humans. Once discovering these types of cells, Leeuwenhoek saw that the fertilization process requires the sperm cell to enter the egg cell. This put an end to the previous theory of spontaneous generation. After reading letters by Leeuwenhoek, Hooke was the first to confirm his ...

  3. Evolution of cells - Wikipedia

    en.wikipedia.org/wiki/Evolution_of_cells

    The eukaryotic cell seems to have evolved from a symbiotic community of prokaryotic cells. DNA-bearing organelles like mitochondria and chloroplasts are remnants of ancient symbiotic oxygen-breathing bacteria and cyanobacteria, respectively, where at least part of the rest of the cell may have been derived from an ancestral archaean prokaryote ...

  4. Timeline of biology and organic chemistry - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_biology_and...

    In 1661, 1664 and 1665, the blood cells were discerned by Marcello Malpighi. In 1678, the red blood corpuscles was described by Jan Swammerdam of Amsterdam, a Dutch naturalist and physician. The first complete account of the red cells was made by Anthony van Leeuwenhoek of Delft in the last quarter of the 17th century.

  5. Timeline of the history of genetics - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_the_history_of...

    In 1871 he isolated cell nuclei, separated the nucleic cells from bandages and then treated them with pepsin (an enzyme which breaks down proteins). From this, he recovered an acidic substance which he called "nuclein". [1] 1880–1890: Walther Flemming, Eduard Strasburger, and Edouard Van Beneden elucidate chromosome distribution during cell ...

  6. History of cell membrane theory - Wikipedia

    en.wikipedia.org/wiki/History_of_cell_membrane...

    In this view, the cell was seen to be enclosed by a thin surface, the plasma membrane, and cell water and solutes such as a potassium ion existed in a physical state like that of a dilute solution. In 1889, Hamburger used hemolysis of erythrocytes to determine the permeability of various solutes. By measuring the time required for the cells to ...

  7. Friedrich Miescher - Wikipedia

    en.wikipedia.org/wiki/Friedrich_Miescher

    The cells were filtered, and since centrifuges were not available at the time, the cells were allowed to settle to the bottom of a beaker. He then tried to isolate the nuclei free of cytoplasm . Miescher subjected the purified nuclei to an alkaline extraction followed by acidification, resulting in the formation of a precipitate that he called ...

  8. The Overdue, Under-Told Story Of The Clitoris

    projects.huffingtonpost.com/projects/cliteracy/intro

    From ancient history to the modern day, the clitoris has been discredited, dismissed and deleted -- and women's pleasure has often been left out of the conversation entirely. Now, an underground art movement led by artist Sophia Wallace is emerging across the globe to challenge the lies, question the myths and rewrite the rules around sex and the female body.

  9. History of biology - Wikipedia

    en.wikipedia.org/wiki/History_of_biology

    The history of biology traces the study of the living world from ancient to modern times. Although the concept of biology as a single coherent field arose in the 19th century, the biological sciences emerged from traditions of medicine and natural history reaching back to Ayurveda, ancient Egyptian medicine and the works of Aristotle, Theophrastus and Galen in the ancient Greco-Roman world.