In smooth muscle, actin and myosin filaments:
A. are organized into sarcomeres and aligned to yield a striated appearance
B. overlap, with the actin filaments anchored at dense bodies
C. overlap, and contain a tropomyosin-troponin complex on the actin filament
D. require phosphorylation of the myosin heavy chain to initiate muscle contraction
E. typically generate contractile force in the absence of cytosolic Ca++
ANS: B
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