ULTIMATE COMPUTING - Quantum Consciousness Studies

112 Cytoskeleton/Cytocomputer
lymphocytes and macrophages are white blood cells which combat infection by
migrating from the blood stream into an open wound to engulf invading bacteria
or foreign material. Cells of developing embryos perform precisely
choreographed movements that give rise to different tissues. Internal movement
such as the streaming of cytoplasm, secretion of cell product vesicles (i.e.
neurotransmitters), engulfment of matter, and the separation of paired
chromosomes in cell division are routine functions whose complexity,
organization, and precision generally boggle biologists.
Also, well controlled muscle contraction which depends on the
conformational bending of myosin head molecules can result in strenuously
running a 4 minute mile, or delicately painting a Mona Lisa. Four categories of
cytoplasmic movement and force generation will be considered with attention to
their regulatory mechanisms. These are: cytoplasmic probing, bending sidearms,
ciliary and collective movements, and geodesic tensegrity structures.
5.5.1 Cytoplasmic Probing
In the early 20th century, W. H. Lewis, an embryologist at Carnegie Institute
of Washington, took time lapse motion pictures of cells grown in culture
(Lazarides and Revel, 1979). Lewis treated the fibroblasts (active cells which
repair wounds) with protein cleaving enzymes to break up adhesive contacts and
networks of extracellular material holding the cells together. He separated the
resulting clumps and grew individual cells in a nutrient medium. After a few
hours, Lewis’ fibroblasts had acquired a polygonal shape. Along the shortest side
of the polygon were lamellipodia, delicate sheet-like extensions of the cytoplasm.
He exclaimed: “the ruffled lamellipodia slowly bend back and forth like the
ruffles of a dress in a slight breeze” (Lazarides and Revel, 1979). Later, Ingram
and Abercrombie at University College London studied the membrane coated
ruffled lamellipodium, fibroblasts’ main locomotion organ. The lamellipodium
forms strings and contacts with the substrate on which the cell rests, stretching
portions of the rest of the cell among several temporary adhesions. When the cell
is spread out to its fullest extent it maintains one or two primary ruffles, each of
which tend to lead the cell in a particular direction. The cell then migrates with
changes in direction which typically come at intervals of several hours. If a ruffle
does not stick and the cell move in another direction, the ruffle folds back on the
upper surface of the cell, collapses onto it and disappears into the cell (Figure
5.22, 5.23 and 5.24).