Sherwood- Chapter 8

Objective:  Contraction in a muscle fiber is accomplished by all the sarcomeres shortening simultaneously.

1.  Sliding filament mechanism
        a.  contraction is accomplished by the thin filaments sliding closer together between the thick filaments
2.  Cross-bridge activity
        a.  ATP is hydrolyzed by myosin ATPase
        b.  calcium is released from lateral sacs
        c.   power stroke of contraction
        d.  actin and myosin break as fresh ATP binds to myosin
3.  Excitation - contraction coupling
        a.  begins with an action potential
        b.  results in cross-bridge activity
4.  Muscle relaxation