Slow Cycling of the Myosin Cross-Bridges. The rapidity of cycling of the myosin cross-
bridges in smooth muscle—that is, their attachment to actin, then release from the actin, and
reattachment for the next cycle—is much slower
Actin filaments Dense bodies Cell membrane Myosin filaments Figure 8-2 Physical
structure of smooth muscle. The upper lefthand fiber shows actin filaments radiating from
dense bodies.
The lower left-hand fiber and the right-hand diagram demonstrate the relation of myosin
filaments to actin filaments.
