plural snack bars. snack bar. noun. plural snack bars. Learner's definition of SNACK BAR. [count] : a public place where small meals and snacks are served usually at a counter. There's a snack bar at the pool where we can get nachos.
All muscles exert their force by pulling between at least two points of attachment. The movement that results from contraction is called the action of the muscle. Typically, one attachment remains stationary and is called the origin and the other attachment moves and is called the insertion. Almost all muscles cross at least one joint (moveable connection between two bones) and cause an action across that joint.
to contraction in skeletal muscle. The trigger for a muscle contraction is an electrical impulse. The electrical signal sets off a series of events that lead to crossbridge cycling between myosin and actin, which generates force. The neurotransmitter crosses the gap, binds to a protein (receptor) on the muscle-cell membrane and causes an action potential in the muscle cell. 2  The action potential rapidly spreads along the muscle cell and enters the cell through the T-tubule.