Fig. 4. Tensegrity cell models composed of sticks-and-strings. (A) A model was suspended from above and loaded, from left to right, with 0, 20, 50, 100 or 200 g weights on a single strut at its lower end. Note that a local stress induces global structural arrangements. Reprinted (abstracted/excerpted) with permission from (Wang et al., 1993) American Association for the Advancement of Science. (B) A tensegrity model of a nucleated cell when adherent and spread on a rigid substrate (left) or detached and round (right). The cell model is composed of large metal struts and elastic cord; the nucleus contains sticks and elastic strings. In this cell model, the large struts conceptually represent microtubules; the elastic cords correspond to microfilaments and intermediate filaments that carry tensional forces in the cytoskeleton.