Which one of the following is absent in smooth muscles?
(C) Troponin> Smooth muscle have no troponin or tropomyosin, but they have actin and myosin.> They have no sarcoplasmic reticulum, No T-tubule.> No Z lines. The contraction is stimulated by extracellular ca+.> Latching - is the characteristic of smooth muscle. Even after the dephosphorylation of myosin, the cross bridges continue to attach in the same position for some time. There is no fixed tension relationship.
Actin
Myosin
Troponin
Myosin adenine triphosphatase
Misc.