ULTIMATE COMPUTING - Quantum Consciousness Studies

80 Cytoskeleton/Cytocomputer
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5 Cytoskeleton/Cytocomputer
Living organisms are collective assemblies of cells which contain collective
assemblies of organized material called protoplasm. In turn, protoplasm consists
of membranes, organelles, nuclei and the bulk interior medium of living cells:
cytoplasm. Dynamic rearrangements of cytoplasm within eukaryotic cells account
for their changing shape, repositioning of internal organelles, and in many cases,
movement from one place to another. We now know that the cytoskeleton, a
dynamic network of filamentous proteins, is responsible for cytoplasmic
organization (Figures 5.1 thru 5.3).
5.1 The Nature of Cytoplasm
The nature of cytoplasm has been scientifically studied for at least a century
and a half. That history was described by Beth Burnside (1974) in a landmark
meeting devoted to the cytoskeleton at the New York Academy of Sciences.
An early French observer of cellular material, Felix Du Jardin proposed in
1835 that all cells were composed of a motile material called “sarcode” that had
both structural and contractile properties. In 1861, Austrian E. Brucke linked the
mechanical and physiological properties of cells to a fundamental organization or
architecture of cytoplasm as distinguished from purely chemical or physical
properties. Early Dutch microscopist van Leeuwenhoek observed that red blood
cells became deformed passing through capillaries Hand then sprang back into
shape, demonstrating the elasticity of cytoplasm. The variety of elaborate forms
that cells assume and maintain also require some cytoplasmic rigidity, properties
which led nineteenth century biologists to conclude that cytoplasm is not merely a
liquid nor an emulsion nor an aqueous suspension of life bearing granules. Rather,
cytoplasmic architecture and contractility could be explained by the proposal of a
mesh-like “reticular” or “fibrous” substructure whose interstices were filled with
fluid. To some early biologists, the structure of cytoplasm therefore consisted of a
continuous reticular network of delicate fibrils extending through the cell
(reticular theory). Others claimed that the fibrils forming the cytoplasmic
substratum were unbranched and discontinuous (fibrillar theory). Both of these
theories were initially supported, but later deflated, by microscope preparation
techniques of fixation and staining which arose between 1870 and 1890. Fibrillar
and reticular frameworks appeared everywhere in many types of fixed cells,
particularly in muscle, nerve, cartilage and epithelial cells.