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Leeuwenhoek discovery of living organisms
Antoni van Leeuwenhoek concluded that particles seen under the microscope were living organisms. This discovery is important because it changed the emphasis of scientific observations and attracted attention to bacteria, microbes, and cells. -
Felice Fontana glimpsed nucleus
Felice Fontana glimpsed the nucleus in epithelial cells but had been observed in animal and plant cells. This is important because it contains genetic material, DNA which is responsible for controlling and directing all the cells activities, also RNA -
Robert Brown sees nucleus as essential
Robert Brown was the first to recognize the nucleus as an essential constituent of living cells. This is important because the nucleus serves the function of information storage, retrieval, and duplication of genetic information. -
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Cell theory officially formulated
The idea of cells being a basic component of living organisms came way before the formulation of cell theory. This is important because it allows us to understand the concept of how organisms are created, grow, and die. which allows us to understand how new life is created, how sickness spreads, why organisms take the form they do, and how some sicknesses can be contained. -
Cells are formed through scission
Robert Remak, Rudolf Virchow, Albert Kölliker showed that cells are formed through scission of pre-existing cells. This is important because it became the basis of the theory of tissue formation even if the mechanisms of nuclear division were not understood at the time. -
Kölliker sensory and motor cells
Kölliker proposed that sensory and motor cells of the right and left
halves of the spinal cord were linked by anastomoses. This is important because the sensory cells carry impulses to a central neuron which makes contact with a motor cell that carries impulses to the effector producing the response. -
Joseph Gerlach central nervous system
Joseph Gerlach proposed that in all of the central nervous system, nerve cells established anastomoses with each other through a network formed by the branching of their dendrites. This is important because the network is an essential element of grey matter that provided a system for anatomical and functional communications from which nerve fibers originated. -
Wilhelm nerve-cell body and prolongations form
Wilhelm put forward the idea that the nerve-cell body and its prolongations form an independent unit. This is important because the nervous system began to be considered, like any other tissue, as a sum of anatomically and functionally independent cells, which interact contiguity rather than by continuity. -
Waldeyer establishment of half chromosomes
Wilhelm Waldeyer established that each half chromosome moves to the opposite pole of the mitotic nucleus, which was also
observed in plants. This is important because it provided further evidence of the deep unity of the living world -
Waldeyer neurons independent cells
Waldeyer introduced the term ‘‘neurons’’ to indicate independent nerve cells. After cell theory as applied to the nervous system became known as the ‘neuron theory’.. This is important because it stated that cells are fundamental discrete units of life.