Contraction
muscle fiber
The involuntary muscle action of the alimentary canal is called peristalsis. It uses this muscle action to move food through.
The primary mover.
antagonist muscle
THe action of the digastric muscle is to depress the mandible or evaluate the larynx
The myofibril is the basic muscle cell, within which is the sarcomere, the basic unit of muscle contraction.
Any physical action that you do can give you muscle. You don't necessarily need weights to gain muscle. Simple things like push ups can still give you muscle.
The frowning action.
Action potential duration in skeletal muscle is around 2 - 5 milliseconds.
The basic "principal" behind somatic motor pathways is a pathway from your "brain" or regions in or near the brain where nerve impluses travel from and go to skeletal muscle to cause a muscle contraction. (It's complicated, but doesn't get any more basic than this) -Jordan Bourne
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