Full 2L QBank
Physiology Smooth Muscle efb4ab05

Smooth muscle contraction due to release of calcium, occurs because of ?

A
Increased cAMP
B
Calcium combining with troponin C
C
Increased cGMP
D
Calmodulin-dependant myosin light chain kinase
High-Yield Explanation
In Smooth muscles, rise in intracellular leads to binding of 4 Ca++ ions with calmodulin. Calcium-calmodulin complex then activates myosin light chain kinase (MLCK). MLCK phosphorylates the regulatory light chain of myosin; this phosphorylation then leads to interaction of myosin with actin. Calmodulin is structurally and functionally related to troponin. Troponin is present in skeletal muscles and initiates contraction by causing a conformational change in the tropomyosin molecule which then uncovers the active sites on the actin filament.

Related Physiology MCQs

Practice 2,00,000+ NEET PG Questions Free

Timed mock tests, mistake queue analytics, audio lectures & zero attempt limits on i❤️Exams.

Start Free Mock Test Now